Files created by J-Cook are not compatible to PHP strict standards.
Strict Standards: Only variables should be assigned by reference
Strict Standards: Non-static method JDom::getName() should not be called statically
Strict Standards: Non-static method JDom::searchFile() should not be called statically
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Sure turing off error reporting is a "solution" but in a development enviroment not very suitable.
If on the messages are very annoying and destroying the layout of the page.