We report on the discovery of a galaxy cluster at z = 1.490 originally selected as an extended X-ray source in the XMM- Newton Distant Cluster Project .
Further observations carried out with the VLT-FORS2 spectrograph allowed the spectroscopic confirmation of seven secure cluster members , providing a median system redshift of z = 1.490 \pm 0.009 .
The color magnitude diagram of XMMU J0338.8+0021 reveals the presence of a well populated red sequence with z - H \approx 3 , albeit with an apparent significant scatter in color .
Since we do not detect indications for strong star formation activity in any of the objects , the color spread could indicate different stellar ages of the member galaxies .
In addition , we found the brightest cluster galaxy in a very active dynamical state , with an interacting , merging companion located at a physical projected distance of d \approx 20 kpc .
From the X-ray luminosity we estimate a cluster mass of M _ { 200 } \sim 1.2 \times 10 ^ { 14 } \mathrm { M _ { \sun } } .
The data seem to suggest a scenario in which XMMU J0338.8+0021 is a young system , possibly caught in a moment of active ongoing mass assembly .