Not sure if this will be of any help. But you could try to install from an RPM or other package: http://rpm.pbone.net/index.php3?stat=3&search=perl-Net-SSH2&srodzaj=3 (yeah I don't see a CentOS or RH9 package)

There's a google groups discussion at: http://groups.google.com/group/comp.lang.perl.modules/browse_frm/thread/f779828508698541/5d51b5dc2a5598e2?lnk=raot&hl=en# (not exactly it either)

I'd do a "make clean" then maybe reinstall libssh2 (not libssl2 like you said) http://www.libssh2.org/ After that I'd start from "perl Makefile.PL" with the install of Net::SSH2.