BUG
Mr.SID MG3 images are not supported by ArcIMS Image Server 4.0, 4.0.1 or 9.0.
Note:
MG3 files are supported by ArcIMS 9.0 using the ArcMap server on Windows only
The needed DLLs provided by the vendor are still in a beta version and cannot be used by ESRI in developing a product.
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