gpg with sylpheed

Hello, I'm using SuSE 7.2 and would like to use gpg with sylpheed as well (I'm using it with kmail for a different account), I installed GPGME 0.2.3 as mentioned in install.txt, I also did ./configure with --enable-gpgme, but it still doesn't work. Why can't sylpheed find the gpgme files, do I have to install them at a special place? Thanks Rubén