Just got this note from 1and1 - scheduled for 2 week of March
What will improve?
Apart from better performance and more security, the migration
to a Linux operating environment (based on Debian Squeeze/6.0)
specifically adapted to the needs of 1&1 and its customers also
includes the upgrade of the following components:
Please note that the migration has resulted in a small number
of changes in the runtime configuration enforced by Apache.
For example, the instruction 'IndexOptions FancyIndex' now takes
you to the function that used to be available under the obsolete
Furthermore if you are using very old scripts or software, please
note that after a redirect by Apache, certain internal variables,
such as 'REMOTE_USER', will henceforth only be available as
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