Dlink DWL-G520+ PCI,antenna problem

Hy! I have this type of wireless PCI card, (dwl-g520+) & i identify this
problem:
the PCI network card, reconize the accesspoint but can't connect with the
network, (i try in the same room for test. ), i try many & many
configuration, also the default config. of the sistem, but nothing. But
there's a strange thing, if i put my hand over the little antenna, or if i
completly remove the antenna, the connection work properly, maybe a problem
of the antenna or card? Anyone have the same problem with PCI DWL-G520+?
By!