After upgrading to Ubuntu 9.10 from 9.04, the GWT plugin for Eclipse doesn’t work so well when trying to run an app in hosted mode.
** Unable to load Mozilla for hosted mode **
java.lang.UnsatisfiedLinkError: /home/igough/installs/eclipse-3.5/plugins/com.google.gwt.eclipse.sdkbundle.linux_1.7.1.v200909221731/gwt-linux-1.7.1/mozilla-1.7.12/libxpcom.so: libstdc++.so.5: cannot open shared object file: No such file or directory
Karmic does not have libstdc++.so.5 as part of the distribution but you can download the one from 9.04 from the Ubuntu repository. I am running 64 bit Ubuntu, and would normally download the 64 bit version of the library, but the GWT Eclipse plugin uses a 32 bit version of Mozilla for hosted mode. And its hosted mode that wants the Standard C++ library. So we must download and install the 32 bit version.
Download libstdc++5_3.3.6-17ubuntu1_i386.deb from the Ubuntu respository link above. Then install using:
> sudo dpkg --install --force-architecture libstdc++5_3.3.6-17ubuntu1_i386.deb
Once you do this, hosted mode should work again.