Without being too unkind to you (and others who still use Perl 4.0), questions of the kind "what can I use in Perl 4.0 are similar to "what can I use under MS/DOS 2.11?" Seriously, you are using a very old version of software. Were Perl a commercial produce, Perl 4.0 would have dropped from support a few years ago. and considering Perl 5.x is free . . .

I have always had the policy of not being in the first 5% of those upgrading to a new version of software, and not being in the last 5% to upgrade as well.