We keep bumping into the useful libraries that are GPL (most recently FFTW, which is GPL with commercial licenses available). My proposal is that we allow dependencies against such libraries as long as - the code which depends on the library is gathered into a self contained module which is, itself, GPL and - IMP as a whole does not require the library to function, only certain functionality is missing
The reason for this suggestion is that - the LGPL, under which we plan to license IMP, allows the code under it to be relicensed under GPL - most people in a research environment will not care if their resulting application is GPL or LGPL - reimplenenting things ourselves is a pain and best put off until we really need to create an application which is not GPL (for example linking with Chimera).