Depth of field is primarily a function of the size of the sensor, and both those cameras have identically sized sensors (1/3"). So the two different cameras, with their respective stock lenses, when shot at the same focal length and the same f-stop, will have the same depth of field.
All 1/3" cameras will have extremely deep depths-of-field, because the sensors are so small. The wider you zoom out, the deeper it will get. At the lens' widest setting the depth of field will be almost infinite.
The only real way to get truly shallow depth of field with a camera like that is to use a lens converter which restores 35mm cinema lens depth-of-field characteristics. This has been discussed in depth in here and in other forums. One recent thread is here: http://forums.creativecow.net/thread/59/856335
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one caveat - the large lens on the XL1 may maintain maximum aperture throughout more of the zoom range. Not sure how the pana compares - but this is certainly true when comparing the XL series to the XH/GL cameras. So when shooting in the middle of the zoom range at maximum aperture the XL may be using a wider aperture, which will render a shallower depth of field.