Dark_AleX has released a new plugin to fool the PS3/PC into thinking that your PSP firmware is whatever the firmware you configure it to be inside of the text file.

For example, you might have 4.01 M33-2, but your PS3 needs you to be on 4.05 to use certain features... So you basically trick it to think you are on that said firmware. This plugin has been made mainly to avoid the PSN downloaders complain about firmware version. - Peza

Instructions: Simply copy seplugins to the root, and activate the plugin in recovery. The plugin will fake the version to the one contained in seplugins/usbversion.txt, which by default is set to 4.05, but you can set it to other versions.
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