Proftpd with PAM and s/key in chroot Er

Hello,
i got a Problem with proftpd on Solaris in a
chroot enviroment with pam and s/key.

Everything is o.k. without s/key modul for pam,when i want to run it with pam and it’s s/key module i got the following Error:

PAM([user]):symbol not found.

Please Help:

rainer.lenz@wwl.de