The reason for this is possibly that you only need 2 pairs for 10Mb and 100Mb. Instead of cutting the wires, why not just loosen them and re-wire everything with all 4 pairs, and then just use stubs from the patchpanel to the switch. Then you can use GigE. In that case, also make sure that the jacks are wired correctly.

Edit: I noticed that they have used a 'wrong' pair in the wiring. They've used the blue pair, which normally is connected to pin 4 & 5. The 'correct' pair should be the green pair.

Stig