multiple versions of development ports

[Dave]

Hello,
    I've got a 6.1 box that i'm trying to install some software on for 
development. The software needs autoconf, automake, autoheader, etc. which 
has been installed in multiple versions autoconf213, 253, 259, the same for 
automake etc. I created symlinks from the say autoconf259 to autoconf so it 
would be found by the configure process, but was wondering if there was a 
better way, such as some option to add to make.conf so that all ports 
utilize a specific version of autoconf or automake as the case may be?
Thanks.
Dave.