How can I save a value in PO cache?

Hi to everyone, My problem is:

I have an integration SOAP to SOAP on PO 7.4,  the first step is obtain a TOKEN, then I want to save this token in cache or PO database, beacuse later I'll can use this token in other operation from other integration.  So I need verify first if a TOKEN exists and if is the case use this TOKEN.

Any idea?

thanks a lot.