Summary form only given. All-optical wavelength conversion can play an important role in future ultra-high-speed networks due to the significant increase in flexibility and potential reduction in need for optical buffers. We have recently demonstrated a different cross phase modulation (XPM) based scheme to wavelength convert 40 Gb/s RZ data. The basic idea of this scheme is to utilize XPM in a dispersion shifted fiber. Continuous wave (CW) light is launched into the fiber along with the data pulses. The pulses will impose a phase modulation which generates sidebands on the CW light. After suppression of the original CW wavelength, and filtering out one of the sidebands, the wavelength converted data remains at the output. Here we report on pulse measurements in the wavelength converter in order to assess its fundamental operating characteristics.