Opening an eml file (from disk) opens a message window. Save as command in the menu and Ctrl-S are disabled. But the context menu still allows it and a Save as dialog is presented. But the actual action to save the message returns an error. Either fix the save operation or disable the menu option.
The save operation should be there I believe. Doesn't this bug depend on https://bugzilla.mozilla.org/show_bug.cgi?id=204350 ?
Yes, but actually this bug doesn't say whether the feature should be there or not, just that the menus are inconsistent. The command should be disabled everywhere, or enabled everywhere. If bug 204350 is fixed and the operation works and the command is enabled everywhere, it fixes this bug.
Saving a message window opened with a .eml file now works for SeaMonkey 2.1a2. See Bug 555972