Index: src/org/openstreetmap/josm/gui/tagging/presets/items/ComboMultiSelect.java
===================================================================
--- src/org/openstreetmap/josm/gui/tagging/presets/items/ComboMultiSelect.java	(revision 19555)
+++ src/org/openstreetmap/josm/gui/tagging/presets/items/ComboMultiSelect.java	(working copy)
@@ -30,6 +30,7 @@
 import org.openstreetmap.josm.tools.AlphanumComparator;
 import org.openstreetmap.josm.tools.GBC;
 import org.openstreetmap.josm.tools.Logging;
+import org.openstreetmap.josm.tools.ReflectionUtils;
 
 /**
  * Abstract superclass for combo box and multi-select list types.
@@ -231,15 +232,29 @@
         String[] classMethod = valuesFrom.split("#", -1);
         if (classMethod.length == 2) {
             try {
-                Method method = Class.forName(classMethod[0]).getMethod(classMethod[1]);
+                Class<?> cl = ReflectionUtils.findClass(classMethod[0]);
+                if (cl == null) {
+                    Logging.error(tr("Broken tagging preset \"{0}-{1}\" - Java class {2} given in ''values_from'' was not found",
+                            key, text, classMethod[0]));
+                    return null;
+                }
+                Method method = cl.getMethod(classMethod[1]);
                 // Check method is public static String[] methodName()
                 int mod = method.getModifiers();
                 if (Modifier.isPublic(mod) && Modifier.isStatic(mod)
-                        && method.getReturnType().equals(String[].class) && method.getParameterTypes().length == 0) {
-                    return Arrays.asList((String[]) method.invoke(null));
-                } else {
-                    Logging.error(tr("Broken tagging preset \"{0}-{1}\" - Java method given in ''values_from'' is not \"{2}\"", key, text,
-                            "public static String[] methodName()"));
+                        && method.getReturnType().equals(String[].class)) {
+                    if (method.getParameterTypes().length == 0) {
+                        return Arrays.asList((String[]) method.invoke(null));
+                    } else if (method.getParameterTypes().length == 1 && method.getParameterTypes()[0].equals(String.class)) {
+                        return Arrays.asList((String[]) method.invoke(key));
+                    } else if (method.getParameterTypes().length == 2
+                            && method.getParameterTypes()[0].equals(String.class)
+                            && method.getParameterTypes()[1].equals(String.class)) {
+                        return Arrays.asList((String[]) method.invoke(key, originalValue));
+                    } else {
+                        Logging.error(tr("Broken tagging preset \"{0}-{1}\" - Java method given in ''values_from'' is not \"{2}\"", key, text,
+                                "public static String[] methodName()"));
+                    }
                 }
             } catch (ReflectiveOperationException e) {
                 Logging.error(tr("Broken tagging preset \"{0}-{1}\" - Java method given in ''values_from'' threw {2} ({3})", key, text,
Index: src/org/openstreetmap/josm/tools/ReflectionUtils.java
===================================================================
--- src/org/openstreetmap/josm/tools/ReflectionUtils.java	(revision 19555)
+++ src/org/openstreetmap/josm/tools/ReflectionUtils.java	(working copy)
@@ -60,6 +60,27 @@
         }, exclusions);
     }
 
+    /**
+     * Find a class either in the default class loader or in plugins.
+     * @param name class name to search
+     * @return found class object, or null if it was not found
+     */
+    public static Class<?> findClass(String name) {
+        try {
+            return Class.forName(name);
+        } catch (ClassNotFoundException e) {
+            Logging.trace(e);
+            for (ClassLoader cl : PluginHandler.getPluginClassLoaders()) {
+                try {
+                    return Class.forName(name, true, cl);
+                } catch (ClassNotFoundException ex) {
+                    Logging.trace(e);
+                }
+            }
+            return null;
+        }
+    }
+
     private static <T> T findCaller(Function<StackTraceElement, T> getter, Collection<T> exclusions) {
         StackTraceElement[] stack = Thread.currentThread().getStackTrace();
         for (int i = 3; i < stack.length; i++) {