[imp] Excessive memory usage

[Andrew Morgan]

I'm using the latest RC releases of Horde and IMP.

One of my users complained that he couldn't view a large message.  The 
message has 11 Appledouble JPEG image attachments that are about 2.5MB 
each.  When he clicked on the message to view it, all he got was a blank 
screen after a short while.

The message size is 34MB, and I found that I cannot display the message 
until I increase the PHP memory limit to 250MB.

The message parts look like this (from Alpine):

     [ Part 2.1, Application/APPLEFILE (Name: "IMG_1210.JPG") 98 KB. ]
     [ Not Shown. Use the "V" command to view or save this part. ]

     [ Part 2.2, Image/JPEG (Name: "IMG_1210.JPG") 2.4 MB. ]
     [ Not Shown. Use the "V" command to view or save this part. ]

Also, it doesn't generate a thumbnail for any of the images and clicking 
on the "view thumbnail" link in its place open a new window but it is 
blank.

If I send myself a new message with the same exact images, but not in 
Appledouble wrappers, then it can display the message and the thumbnails 
correctly even with the PHP memory limit set to 100MB (our production 
setting).

Looking through the Appledouble viewer code in IMP, I'm guessing that 
there are simply too many copies of the same data being made, bloating the 
memory size.

Is this a known issue/bug?

 	Andy