wp with demon hosting =incompatible?

ok.. so i changed my permalink structure to use index.php?p=1 and all my links go to my first post, but if i set it to index.php i just get ‘no input file specified’ problems.. AFAIK my server does not have mod_rewrite but it is apache, so will wordpress never work on my server or are they possible workarounds? I use WP 1.5.1.2 and host with https://www.demon.net

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