DMA interrupts

Hi, I'm trying to get DMA interrupts to work.  Here's my code:

main()
{
_enable_interrupt_();

....

dmaEnableInterrupt(SPI1_DMA,FTC);

}

void dmaNotification(dmaBASE_t *DMA, uint32 flags)
{
while(1);
}

I've also enabled VIM channel 33 (DMA FTC) in HalCoGen.  Unfortunately, my ISR is never reached.  The DMA is definitely working, so it would seem to be my interrupt configuration which is wrong.  Any ideas?

Thanks,

Jack