Mime Type restricted to 32 Characters

I am trying to add the mime types for Office 2007 from the Edit Mime Type screen

application/vnd.openxmlformats-officedocument.presentationml.presentation pptx

But when it saves it in the database it is saving only the first 32 characters.

The problem comes while trying to generate a thumbnail for which it is not able to recognize and match it.

Debug info on saving included below

>>>>>>>>>

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file_exists(/var/www/html/gallery2-2/g2data/cache/module/_all/0/0/GalleryMimeTypeHelper_mimeData.inc)
is_dir(/var/www/html/gallery2-2/g2data/cache/module/_all/0/0/GalleryMimeTypeHelper_mimeData.inc)
unlink(/var/www/html/gallery2-2/g2data/cache/module/_all/0/0/GalleryMimeTypeHelper_mimeData.inc)
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(mysqli):
SELECT
g2_MimeTypeMap.g_extension
FROM
g2_MimeTypeMap
WHERE
g2_MimeTypeMap.g_extension = 'sujoy1'
LIMIT 1
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(mysqli): INSERT INTO g2_MimeTypeMap (g_extension, g_mimeType, g_viewable)
VALUES ('sujoy1','application/vnd.openxmlformats-o',0)
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file_exists(/var/www/html/gallery2-2/g2data/cache/module/_all/0/0/GalleryMimeTypeHelper_mimeData.inc)

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