Always use <?php ?> to delimit PHP code, not the <? ?> shorthand. This is required for Mambo compliance and is also the most portable way to include PHP code on differing operating systems and setups.
Note that the final ?> should be omitted from all code files--modules, includes, etc. The closing delimiter is optional, and removing it helps prevent unwanted white space at the end of files which can cause problems elsewhere in the system.
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