I feel for you. I really do. Something like that sounds like the best course of action is to quietly start job hunting ;-)

On a more practical note, when you're in a catch-22 situation, I always recommend talking it over with your manager. Your manager may be a total arse, or a wonderful angel, I don't know. Never met the person. I am pretty sure, however, that s/he is being paid to make these types of decisions. Point out the conflicts in your requirements vs the business reality you're working within. Let your manager decide which is more important between secure LDAP, fighting with the other department, time, and resource. That's a manager's job. Your job, as a non-manager, is to simply be transparent in all that you do: evaluate your requirements, implement them where you can, and alert your manager ASAP when you cannot.

IMO, you're very likely at that point where you've determined that you cannot. You need to get OpenSSL and Perl compiled with the same compiler. Perhaps your manager will go with the idea of getting the IBM C compiler so you can get OpenSSL compiled with that.

You know, it strikes me as somewhat odd that a company trying to go to secure LDAP would be running AIX 4.3 anywhere. If security is a priority, wouldn't that also include sticking with supported operating systems? AIX 4 went out of service a while ago - we have to go through hoops to get our IT dept to allow us to keep our AIX 4 machines, despite the fact that we still support our product on AIX 4 (as long as it isn't an OS problem ;->).

Update: You should also get in the habit of getting managerial decisions, especially ones that may come back to haunt you, in writing, or whatever passes for "in writing" in your company. e.g., in our company, using Lotus Notes, all emails are automatically electronically signed, so simply getting an email from my manager about something is as good as "in writing". CYA at all times :-)