Does anyone know how to connect to informix(Solaris) from windows using perl scripts over the network?

I never used Informix myself, but the usual way is DBI/DBD::Informix.

You might encounter the problem of compiling DBD::Informix yourself, as there is no compiled version at activestate.

If you don't find a compiled version and can't compile it on your own, try DBD::Proxy. It comes with DBI.