if that library is installed

If the curl executable is installed and working how could the library not be present? I suppose they could have a statically-compiled curl but I've never seen that in the wild.

and a C compiler is installed

Good point. That's the much more likely blocker I think. If I were Yahoo (and thank the Old Gods and the New that I am not) there wouldn't be a compiler on these customer-accessible nodes either.

Is there a pure-perl SSL implementation somewhere on CPAN or did I just dream that?