diff -r cc93757aeca3 -r 6dcaece8ec41 hack/model/TimeZoneRegistryImpl.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hack/model/TimeZoneRegistryImpl.java	Fri Feb 13 23:45:37 2015 +0100
@@ -0,0 +1,220 @@
+/**
+ * Copyright (c) 2012, Ben Fortuna
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *  o Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ *  o Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ *  o Neither the name of Ben Fortuna nor the names of any other contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package net.fortuna.ical4j.model;
+
+import java.io.IOException;
+import java.net.URL;
+import java.util.Map;
+import java.util.Properties;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+import net.fortuna.ical4j.data.CalendarBuilder;
+import net.fortuna.ical4j.data.ParserException;
+import net.fortuna.ical4j.model.component.VTimeZone;
+import net.fortuna.ical4j.model.property.TzUrl;
+import net.fortuna.ical4j.util.CompatibilityHints;
+import net.fortuna.ical4j.util.Configurator;
+import net.fortuna.ical4j.util.ResourceLoader;
+
+import android.util.Log;
+
+import edu.emory.mathcs.backport.java.util.concurrent.ConcurrentHashMap;
+
+/**
+ * $Id$
+ *
+ * Created on 18/09/2005
+ *
+ * The default implementation of a <code>TimeZoneRegistry</code>. This implementation will search the classpath for
+ * applicable VTimeZone definitions used to back the provided TimeZone instances.
+ * @author Ben Fortuna
+ */
+public class TimeZoneRegistryImpl implements TimeZoneRegistry {
+
+    private static final String DEFAULT_RESOURCE_PREFIX = "zoneinfo/";
+
+    private static final Pattern TZ_ID_SUFFIX = Pattern.compile("(?<=/)[^/]*/[^/]*$");
+    
+    private static final String UPDATE_ENABLED = "net.fortuna.ical4j.timezone.update.enabled";
+
+    private static final Map DEFAULT_TIMEZONES = new ConcurrentHashMap();
+
+    private static final Properties ALIASES = new Properties();
+    static {
+        try {
+            ALIASES.load(ResourceLoader.getResourceAsStream("tz.alias"));
+        }
+        catch (IOException ioe) {
+			Log.w("MSvB-Hack", "Error loading timezone aliases: " + ioe.getMessage());
+        }
+        try {
+        	ALIASES.load(ResourceLoader.getResourceAsStream("/tz.alias"));
+        }
+        catch (Exception e) {
+			Log.d("MSvB-Hack", "Error loading custom timezone aliases: " + e.getMessage());
+        }
+    }
+
+    private Map timezones;
+
+    private String resourcePrefix;
+
+    /**
+     * Default constructor.
+     */
+    public TimeZoneRegistryImpl() {
+        this(DEFAULT_RESOURCE_PREFIX);
+    }
+
+    /**
+     * Creates a new instance using the specified resource prefix.
+     * @param resourcePrefix a prefix prepended to classpath resource lookups for default timezones
+     */
+    public TimeZoneRegistryImpl(final String resourcePrefix) {
+        this.resourcePrefix = resourcePrefix;
+        timezones = new ConcurrentHashMap();
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public final void register(final TimeZone timezone) {
+    	// for now we only apply updates to included definitions by default..
+    	register(timezone, false);
+    }
+    
+    /**
+     * {@inheritDoc}
+     */
+    public final void register(final TimeZone timezone, boolean update) {
+    	if (update) {
+            // load any available updates for the timezone..
+            timezones.put(timezone.getID(), new TimeZone(updateDefinition(timezone.getVTimeZone())));
+    	}
+    	else {
+            timezones.put(timezone.getID(), timezone);
+    	}
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public final void clear() {
+        timezones.clear();
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public final TimeZone getTimeZone(final String id) {
+        TimeZone timezone = (TimeZone) timezones.get(id);
+        if (timezone == null) {
+            timezone = (TimeZone) DEFAULT_TIMEZONES.get(id);
+            if (timezone == null) {
+                // if timezone not found with identifier, try loading an alias..
+                final String alias = ALIASES.getProperty(id);
+                if (alias != null) {
+                    return getTimeZone(alias);
+                }
+                else {
+                    synchronized (DEFAULT_TIMEZONES) {
+                    	// check again as it may be loaded now..
+                    	timezone = (TimeZone) DEFAULT_TIMEZONES.get(id);
+                    	if (timezone == null) {
+                            try {
+                                final VTimeZone vTimeZone = loadVTimeZone(id);
+                                if (vTimeZone != null) {
+                                    // XXX: temporary kludge..
+                                    // ((TzId) vTimeZone.getProperties().getProperty(Property.TZID)).setValue(id);
+                                    timezone = new TimeZone(vTimeZone);
+                                    DEFAULT_TIMEZONES.put(timezone.getID(), timezone);
+                                }
+                                else if (CompatibilityHints.isHintEnabled(CompatibilityHints.KEY_RELAXED_PARSING)) {
+                                    // strip global part of id and match on default tz..
+                                    Matcher matcher = TZ_ID_SUFFIX.matcher(id);
+                                    if (matcher.find()) {
+                                        return getTimeZone(matcher.group());
+                                    }
+                                }
+                            }
+                            catch (Exception e) {
+                                Log.w("MSvB-Hack", "Error occurred loading VTimeZone", e);
+                            }
+                    	}
+                    }
+                }
+            }
+        }
+        return timezone;
+    }
+
+    /**
+     * Loads an existing VTimeZone from the classpath corresponding to the specified Java timezone.
+     */
+    private VTimeZone loadVTimeZone(final String id) throws IOException, ParserException {
+        final URL resource = ResourceLoader.getResource(resourcePrefix + id + ".ics");
+        if (resource != null) {
+            final CalendarBuilder builder = new CalendarBuilder();
+            final Calendar calendar = builder.build(resource.openStream());
+            final VTimeZone vTimeZone = (VTimeZone) calendar.getComponent(Component.VTIMEZONE);
+            // load any available updates for the timezone.. can be explicility disabled via configuration
+            if (!"false".equals(Configurator.getProperty(UPDATE_ENABLED))) {
+                return updateDefinition(vTimeZone);
+            }
+            return vTimeZone;
+        }
+        return null;
+    }
+    
+    /**
+     * @param vTimeZone
+     * @return
+     */
+    private VTimeZone updateDefinition(VTimeZone vTimeZone) {
+        final TzUrl tzUrl = vTimeZone.getTimeZoneUrl();
+        if (tzUrl != null) {
+            try {
+                final CalendarBuilder builder = new CalendarBuilder();
+                final Calendar calendar = builder.build(tzUrl.getUri().toURL().openStream());
+                final VTimeZone updatedVTimeZone = (VTimeZone) calendar.getComponent(Component.VTIMEZONE);
+                if (updatedVTimeZone != null) {
+                    return updatedVTimeZone;
+                }
+            }
+            catch (Exception e) {
+                Log.w("MSvB-Hack", "Unable to retrieve updates for timezone: " + vTimeZone.getTimeZoneId().getValue(), e);
+            }
+        }
+        return vTimeZone;
+    }
+}