Description:
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This is essentially the same problem as described in #46731 and #46837.
The values of options passed to imap functions are not checked precisely.

Patches for:
imap_body(),imap_fetchstructure(),imap_fetchbody(),imap_fetchheader()

Are here:
http://www.pastebin.ca/1286942
http://www.pastebin.ca/1286943
http://www.pastebin.ca/1286944


I have also fixed missing initialisation of flags in fetchheader() in PHP53 and PHP6.


Reproduce code:
---------------
Test cases here

http://www.pastebin.ca/1286945
http://www.pastebin.ca/1286947
http://www.pastebin.ca/1286948
http://www.pastebin.ca/1286949

Expected result:
----------------
As shown in test cases

Actual result:
--------------
PHP_INT_MAX is accepted as a valid option.