PR_Read fails second time on Solaris 8

Hi,

We are using NSPR/NSS for SSL communication on Solaris8.

Right now, we are using it as a client to communicate to another SSL server 
running on windows.
However my PR_Read call returns with 0, when its called a second time.
The first calls succeeds and returns me some data in the buffer.

Can anybody throw some light as to what is going wrong here?

Thanks
Vinu