Does the mapset name "gmapsup2" work on ALL garmin xt installations????????

I use "gmapsupp" more or less as a temporary mapset to load tracks, routes and POI's etc into xt & "gmapprom" (as my primary mapset which has 3 maps combined).

I'd like to have one other (ie gmapsup2) but XT wont recognize it (basecamp has no such problems????)