Hiya, just a quick note to say that wepdecrypt builds the wkeygen file with the libraries listed before the wkeygen.c file. That means that --as-needed removes the libraries before they're referenced causing errors during the linking stage. The patch simply re-arranges where the $(LIBS) argument comes in the Makefile.
Created attachment 125726 [details, diff] wepdecrypt-0.8-as-needed.patch
Ok, just committed the fix. Please re-open this bug if there are any problems with the patch... 5:)