To stupid to implement an ISR for XISR, PE<0>

Hi,

on our DEMO9S12NE64-Board are two switches, SW1 and SW2. I want to
react to SW1, which was connected to PE<0>, XISR. I wrote a function:

void interrupt 5 ButtonPressed(void)
{}

and added the line in monitor.prm:

VECTOR 5 ButtonPressed

When i compile the project i get the Linker Error:

Link Error   : L1119: Vector allocated at absolute address 0xFFF4
overlaps with sections placed in segment .absSeg0

Can anybody explain me my problem or give me a little example for
reacting for an interrupt?

Many Thanks

Volker