Polarisation-independent, stable 100 Gbit/s operation of an all-optical time-domain demultiplexer is demonstrated at 1.55 mu m, using four-wave mixing frequency conversion in a polarisation-maintaining fibre loop. Error-free 100 to 6.3 Gbit/s demultiplexing is achieved by a 380 mW, 5.3 ps pulse pump from a modelocked Er/sup 3+/-doped fibre ring laser. The conversion efficiency is 58% and the polarisation dependency is less than 0.5 dB. >