If I have an uncompressed .AVI file that I created in After Effects CS5.5 which is 23.976 fps, and load it in Adobe Media Encoder CS5.5, and tell it to create a .GIF of it, at an output fps of 23.976, when I load the created .GIF into Adobe After Effects it tells me the frame rate is 25 fps and there is a black frame padded on the end.  I want the frame rate of the GIF to be what I ask it to be, ie. 23.976, with no additional black frames.

Here's what happened with screenshots:

1. I load the uncompressed AVI file that was created in Adobe After Effects CS5.5 into Adobe Media Encoder CS5.5.  Note below that Adobe Media Encoder is saying that the source clip is 23.976 fps, and that the export settings are to create an animated GIF at 23.976 fps.

2. After Adobe Media Encoder CS5.5 has said "done" (Encoding Completed Succesfully) for this export to a .GIF, if I take that .GIF file that Adobe Media Encoder has just created into Adobe After Effects CS5.5, this is what it says:

As can be seen above, Adobe After Effects CS5.5 is saying the GIF file that Adobe Media Encoder CS5.5 has just encoded is actually 25 fps, not 23.976 fps like I told it to be exported as.  Also, the GIF Adobe Media Encoder has created is 10 frames long, whereas my original uncompressed AVI is 9 frames long.

Edit: I've just been reading up on the GIF format and it seems it doesn't store a frame rate but instead stores a frame delay, which is in hundredths of a second.  If this is just an integer, is this the reason for the displayed frame rate discrepancy, ie. 1 frame at 23.976 fps  would be 4.1708 hundredths of a second I think, and 1 frame at 25 fps would be 4 hundredths of a second I think - both rounded to the nearest integer would be 4 hundredths of a second so would the frame delay be set to "4" for both 23.976 fps and 25 fps? (there is also the fact that some short time will be taken for the drawing of the frame)

Though even with the above, it shouldn't be increasing the amount of output frames.  It converts it correctly (no additional frames) if I use VirtualDub to convert the AVI to GIF instead of Adobe Media Encoder CS5.5.