You need to edit the Xprotect.meta.plist located here
/System/Library/CoreServices/CoreTypes.bundle/Contents/Resources/XProtect.meta.p list
.plist is one word
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>JavaWebComponentVersionMinimum</key>
<string>1.6.0_37-b06-435</string>
<key>LastModification</key>
<string>Thu, 31 Jan 2013 04:41:14 GMT</string>
<key>PlugInBlacklist</key>
<dict>
<key>10</key>
<dict>
<key>com.macromedia.Flash Player.plugin</key>
<dict>
<key>MinimumPlugInBundleVersion</key>
<string>11.3.300.271</string>
</dict>
<key>com.oracle.java.JavaAppletPlugin</key>
<dict>
<key>MinimumPlugInBundleVersion</key>
<string>1.7.11.22</string>
</dict>
</dict>
</dict>
<key>Version</key>
<integer>54</integer>
</dict>
</plist>
Change
<string>1.7.11.22</string>
to whatever version you are using.
But, if this is Snow Leopard, I would strongly suggest getting at least 1.6.0_37, which is installed with Java Update 10.6 Update 11. This is at least the latest version available from Apple. There is a more recent update from Oracle, but for Snow Leopard it needs to be distributed by Apple, and it may never be.
And be extremely careful where you allow Java to run. Your decision; you're on your own.