Yup, it's harder to get bokeh with a P&S than with a dSLR, but getting a narrow DoF is about more than just aperture and sensor size. A couple things you can try to increase the out of focus blur (in addition to using the largest aperture/smallest f-number you can) are:
- Zoom in - a longer focal length exaggerates out of focus blur (footnote: it does not decrease the DOF).
- Try macro mode and get close to your subject, oof blur increases the closer you are to your subject.
- Make sure the background is separated from your subject--the farther away the background is, the blurrier it will get.