Browsing USB hard drive with Konqueror makes it readonly

Binary package hint: konqueror

I have a Western Digital 250 GB "My Book" external hard drive that connects up via USB2. I'm running Kubuntu Edgy. The drive is formatted as FAT32.

I can mount it fine, either manually using mount or pmount, or by letting Kubuntu automatically mount it by plugging it in. But, when I browse the drive's contents in Konqueror after mounting, I suddenly cannot write to the drive anymore. The whole thing becomes read-only.

In other words, things will go like this:

1) Mount volume.
2) Test volume is writable by using "touch" on a file on the volume. File is successfully touched.
3) Open Konqueror and browse filesystem on drive.
4) Attempt to "touch" the same file again. Operation now fails with this error:

"touch: cannot touch 'file.txt': Read-only file system"

My reporting of this behavior on the Ubuntu Forums spawned a long thread, where we tried lots of different settings in fstab and mount, none of which solved the problem:

http://www.ubuntuforums.org/showthread.php?t=289366

I'm beginning to believe this is a bug in Konqueror, or at least a misconfiguration somewhere in my version of Konqueror, as the problem is consistently reproducible: the volume mounts as writeable, but browsing it in Konq flips it to read-only.