SSL_accept hangs... sometimes ( C, linux, openssl )

I'm currently working on an embedded linux system. There are two crucial client applications on the system that connect to an external server ( on another embedded system, all written in C ). The two apps use different certificates.

The ssl connection works... At least usually, but from time to time an error occures: the server hangs on SSL_accept() when accepting connection from one of the applications - the one using older certificates. Restarting the server application does not help, nor does restarting the client - the only way is to reboot the server system, unless I create a symbilic link to the new certificates used by the other app - only then will restarting the server app work.

Nev开发者_运维问答er does the error occur when both applications use the same, new certificate.

Could this happen due to some strange openssl cache or something like that?