[_m3]

http://www.mozilla.org/start/1.0/faq/profile.html#7.6

7.6. Can I share a profile with my copy of Netscape 6.x, or with an earlier version of Mozilla?

Do not share a profile with Netscape 6. Sharing profiles between different versions of Mozilla can lead to profile corruption – this includes sharing a profile with a version of Netscape based on a different version of Mozilla.

Netscape 6.1 is based on Mozilla 0.9.2, and Netscape 6.2.x is based on Mozilla 0.9.4. The forthcoming Netscape 7.0 will be based on Mozilla 1.0, but sharing your Mozilla 1.0 profile with it is not recommended.