I successfully got the kcachegrind backend callgrind 0.9.8 (for valgrind 2.1.2) working with 1.9.50 working recently. There were two little problems in getting it going, soffice run under callgrind would crash out during startup which was because OOo finds out its own command line from /proc which picks up the callgrind line. The second is that without using –separate-threads=yes to callgrind it would appear as if no calltree output had been generated by callgrind.
A pair of hacky patches to sal and the soffice to get it running are available here
I played with soffice –env:INIFILENAME=… to workaround the first problem but apparently the commandline is used for more than just that purpose, so I just hacked sal instead.