Last night we went from Rls 6.o to 7.5. After we did the Nortel Conferencing stopped working. All three conferencing cards stopped working with 7.5. Put one side back to 6.0 and two of the conferencing cards started to work again. Don't want to fall back to 6.0 as we would have to rebuild all of our IP sets. Any ideas to try as to 7.5 & conferencing not working?. Any ideas are much appreciated.