BREW SDK version 1.0 includes support for animated BMP. This is done by placing the frames side-by-side and specifying the width of each frame with IIMAGE_SetParm with the IPARM-CXFRAME flag. Please see the IIMAGE example in the Examples directory

BREW SDK Version 1.1 has added support for BREW Compressed Image (BCI) animation. A BCI file contains one or more compressed small graphic image(s), each with a specified duration in milliseconds. The duration represents how long you want each image to be shown before it is replaced by the next image in the series. You can use the BCI Authoring Tool included in BREW SDK Version 1.1 to create your BCI file. Please refer to 'Using the BREW Compressed Image Authoring Tool' document included in the SDK for more information.