Hi, the mathcommand defintion in line 151 misses a "colon" in its name. \definemathcommand [approxcoloncolon] [rel] {\approx\coloncolon\colonsep} -\definemathcommand [colonsim] [rel] {\coloncolon\colonsep\sim} +\definemathcommand [coloncolonsim] [rel] {\coloncolon\colonsep\sim} \definemathcommand [simcoloncolon] [rel] {\sim\coloncolon\colonsep} Wolfgang