Latest version of aspell fully supports UTF-8 texts (but internal encoding is still 8-bit and will be in the future too). Latest 0.50.5 does not, so you should use the development snapshot at this time. Thus this seems to be a focus for post-FC2.
I have SRPMS packages ready (ie SPEC file fixes): ftp://ftp.vslib.cz/pub/local/milan.kerslager/RHEL-3/test/ ftp://ftp.linux.cz/pub/linux/people/milan_kerslager/RHEL-3/test/ After some testing they will be moved to RPMS and SRPMS directory.
the next version (FC3) will include the release version of aspell that fully supports UTF-8; aspell unfortunately touches too many things to change it this late in the release cycle