From Dr Twister msg board:

Within the last 4 patches, Verant has created a new bug involving
teleports. Apparently if you portal (Wiz or druid, not the normal "Gate"
spell) within the same zone you become trapped in the zone and unable to
zone out, unless you gate out or log. When you try to zone, it puts you in
the zones "safe" spot.

Quick example to test this is in Greater Faydark cast Fay Gate or Fay
portal (the bug affects group members) and then try to zone into lesser
faydark.

Obvously, there are some exploits connected to this problem in zones like
North Karana, where you can "zone" the mob and get teleported far away for
a free rest.