I've identified the following problem on the UPnP Software of N93:
The software browses the content directory of GMediaServer 0.12 well, but when in the same network thereis a GMediaRenderer 0.4 running, the N93 UPnP software (the gallery one) crashes before list (browse) the mediaserver content.
However, this same configuration (gmediaserver 0.12 and gmediarenderer 0.4) seems to be work fine with the following software (control points)
Cidero MediaControler 1.5
e o Nokia Media Streamer for 770
Then, probably, the problem is in the N93 UPnP control point implementation.