In general its a bad idea, both MAOI's and SSRI's slow down the metabolism of serotonin, making it linger in the synaptic gap for longer, and with the increased levels of serotonin caused by E, takin an anti depressent on top of ecstasy may cause you to get serotonin syndrome, which can be fatal.
http://www.answers.com/topic/seroton...rome?method=22