Q) I seem to have a conflict with another plugin that has the same prefix "gwt". How do I use multiple repositories that have different plugins with the same prefixes?

If you get errors that indicate the plugin does not exist, such as: "The plugin 'org.apache.maven.plugins:maven-gwt-plugin' does not exist or no valid version could be found", it may be because you have another repository enabled that has a different plugin with the gwt prefix.

To work around this (if you need both repos), try using the fully qualified name for the GWT-Maven plugin:

mvn com.totsp.gwt:maven-googlewebtoolkit2-plugin:gwt

(Taken from http://code.google.com/p/gwt-maven/wiki/M2FAQ)