It looks like pine is expecting /bin/passwd when you use it to change your system password. This will not work as /bin/passwd does not exist by default. Of course, a simple link (or telling people not to use that feature) is a nice workaround but I thought this should be mentioned.
Using pine to change your system password? Exactly how do provoke this error?
After starting up pine, choose SETUP from the Main Menu. After choosing SETUP, you can select from the sub-menu at the bottom of the screen. Choose 'N' for Newpassword and it attempts to execute /bin/passwd to change your unix password. I didn't know about this feature til a user brought it up. Doesn't seem like a good place to change your password, but I guess for the shell clueless, it'd work.
Thanks. Fixed in pine-4.21-24... I wouldn't recommend it as a password changing program, though ;).