I simply changed the deps for multi-aterm, and it installs to modular X just fine (on ~x86). Enjoy.
Created attachment 80973 [details] Revised ebuild for modular X. Untested for non-modular X.
Take a look at the ebuild I put in Portage, since you have quite a few more dependencies than I do. Where did you get the extras from?
Fixed, pending further comments.