We've been running Confluence 2.2.9 for a while using the default global logo. After upgrading to 2.5.1, I decided to use our corporate logo as the global logo. After uploading and activating our global logo, we get random page load failures in Firefox 2.0.0.3. It manifests with Firefox prompting to download the page instead of display it (the content-type is set to application/octet-stream?). If i choose to download, the file does not get saved. I have not managed to reproduce the problem in IE 6. Switching back to the default global logo or turning off the global logo solves the problem. I see no exceptions in the log file (but full debug logging is not enabled). The access log reports no abnormal page responses (just 200, 302, and 304).

I've attached the file I use. Let me know what debug logs to turn up if anything may be of help.