So it is indeed possible that the Argeo RPM plugin is broken on 32 bit
As per http://icedtea.classpath.org/bugzilla/show_bug.cgi?id=405 the old default plugin (which is the one built for 32 bits in Argeo's RPMs) is not supported anymore.
The NPP plugin is now the supported version which may explain why the 64bits is still working (more or less) and the 32 bits would be broken.
So maybe a simple rebuild based on the existing specs files and using the NPP plugin for 32 bits as well could already give at least basic support (as in 64bits). Using the latest version maybe a bit harder and require more analysis. I'll let you know.