Found this on maxconsole, (thanks JAMESBDX) I have attached all the files I have used to get this running on SE-B'' but be warned, if you have a custom gameboot, you may not have the room to install the extra prx files to flash and keep your gameboot - i had to do a clean install of SE-B'' first to get it fully working.

Files and version of PSP Filer I Used below
http://www.sendspace.com/file/ru4c5b


2.71/2.80 hybrid firmware direct load working on SE-B!!!

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ok before i start, there is one small con to this method : this flashes your firmware, i am in no way responsable for any bricks


the advantages :

1) no need for devhook, this is direct from XMB!
2) works with no umd in drive!!!

installation (the tricky part)

1) i presume you're on se-b" so i won't dwelve into that
2) you need four 2.80 prxes which are :
- mscm.prx ........ rename it to mscm_280.prx
- mesg_led.prx........ rename it to mesg_led_280.prx
- registry.prx......... rename it to registry_280.prx
- utility.prx........ rename it to utility_280.prx
Place these four renamed prxes in the root of your memory stick.
3)you need psp filer (1.9 is the latest, google it) in the game150 folder

now this is EXACTLY the instructions i used for this to work, as i said before if you're unsure what you're doing don't bother! and i won't be reliable for any OMFG! i've got a brick etc etc posts. now to continue...

4)open psp filer (for english language press select, o, x) and enter hacker mode (L + dpad left + R)
5)you should see that you're in ms0 and hopefully you'll see at the bottom of your list the four prxes.
6)highlight all four (by pressing square on each one) and then press x
7)you should see a copy to ramdisk option with circle show up, if so press circle. once copied press circle again
8)now press start several times until you see you're in flash0
9)you'll see the kn folder, place your arrow on it and press x
10)you should see the option "paste all folders from ramdisk" with circle. if so press circle and press again circle to exit
11)press select + start to leave psp filer
12)if you return to xmb, it's a good sign everythings worked okay.
13)plug in the usb and create a folder in msroot called reflash and paste the attached pspbtcnf_game folder inside
14) shut off your psp and go to recovery mode. go to advanced, flash pspbtcnf_game.txt (2.71) and press x. WARNING, it's important you don't screw this part up so make sure it reads what i just wrote
15)go back to your xmb and run your game!!!