All DFN numbers (e.g. DEXADD) are currently converted using UString::toULong and later casted to signed if necessary. But unfortunately the gcc standard library doesn't convert the string '-1' to 0xffffffff when parsed as an unsigned long. I've just replaced all occurences of negative numbers by the corresponding unsigned bit representation, but thast isn't exactly readable
A new Datatype DFN_SIGNED and an extended sectData field would be possible, but perhaps there is a simpler solution?