Slepc interface problem, IPNorm: The inner product is not well defined!

[Umut Tabak]

Dear all,
I have a generalized eigenvalue problem where B is a singular 
matrix(rather more problematic there are some columns and rows with 
zeros due to a finite element modelling issue.). I read section 3.4.4 of 
slepc manual on the purification, however i could not understand much 
about the details. But I guess, I should use as problem type, 
EPS_PGNHEP, however, I am still getting a "IPNorm: The inner product is 
not well defined!" error. Can someone/developers shed some light on this?
Best regards,
Umut