ppp link activated on startup

Hi,

I'm using debian woody with ppp-on-demand, which worked fine.

But after compile-install postgresql 7.4.1 with postgis, ppp link is
activated on startup, which is very unpleasant. In postgresql.conf
tcpip_socket is set to false.

I'm shure this is a postgresql affair, since removing postgresql rc
scripts corrects this problem. But no more postmaster running at startup
:-(

I think any attempt to connect to postmaster is firing up the ppp link.

What the matter is? What could I do? Where the connection try comes
from? Where it try to go? By knowing it, may be I could to add a rule to
ppp's active-filter.

Thanks

Roman