Invalid phone number when receiving text message from provider

[aschoneveld]

When I am receiving text messages from my mobile provider (KPN in Netherlands) the phone number cannot be parsed and an error is thrown:
"Phone number invalid, only numbers and '+' prefix allowed"
This is caused by the fact that in TXSMSPacket.java the phone number is matched against:
"^\+?\d+$"
Since the phone number field from my provider apparently contains the text "KPN" a text message from this provider can never be received.