Hi, I can confirm that rebuilding gts (#660492) fixed the build of gerris (#652258). Maybe binNMUs of gts on all arches is the right thing for wheezy? All binary packages are arch specific, except for libgts-doc which can be kept as is. (But another sourceful upload would have a similar effect.) Rising the severity of #660492 since it blocks #652258 (serious). Thanks, Roland