We tested this component on php 5.3.
What version of php do you have?
If I look on php 5.4, there is newly E_STRICT as part of E_ALL
error_reporting = E_ALL & ~E_DEPRECATED & ~E_STRICT
I really don't know what else can create this type of error. If this settings for error_reporting will not help, maybe VirtueMart or any other component is overwriting error_reporting settings.
You had never such errors with any other component you've installed, but you are also first one, who get this type of error and php.ini has no effect on it.
If my last advice will not help, then please, send us ftp access and admin access to
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, so we can check, what causes this problems.