I am quite familiar with that remote, and as far as I know there are no ready-made solutions.
When holding a button, the remote continually sends a UART (i.e. RS232 type serial) stream using IR.
It probably sends the data too fast for the HT IR Link (since the NXT would need to use I2C to constantly keep reading the Rx buffer).
You probably aren't looking for a DIY type of solution, but you would probably need a custom receiver (e.g. an Arduino with a TSOP1138). Another possibility would be to connect the TSOP1138 to the RS485 port of the NXT, and parse the data on the NXT (which would probably be fairly resource intensive without the use of interrupts).