in reply to Re^3: \b in Unicode regex
in thread \b in Unicode regex

That's not really important, now that the issue is solved. However, that substring does indeed appear twise. I don't know if your browser works like mine, but if it does, then the substring you refer to occurs in the third line of the big string I posted, and the second occurance is in the 7th and 8th lines (my browser prints a + sign at every linebreak. Maybe that's what confused you).

Again, thank you all Monks for your time and help.