XMM Monitoring of the Evolving AXP 4U 0142+61

4U 0142+61 is a 8.7s anomalous Xray pulsar which, in data from our RXTEmonitoring program, shows pulsations that are slowly but steadily gettingbrighter. Since 2000, the pulses have brightened by approximately 50%. Inconcert with the brightening, the pulse profile is clearly evolving on acomparable time scale. This behavior is unprecedented for an AXP and challengesthe current magnetar model. We request two XMM observations of the source inCycle 5 in order to monitor its phaseaveraged flux and its spectrum, to try toshed light on the physical origin of this behavior. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]