You'll need POLUtils, which is available here:
http://users.telenet.be/pebbles/news.html
Start up FFXI and go to a clean macro set, and put something autotranslated in there, exit the macro editor, and go to a different set (to force FFXI to save what you just did).
Hop over to POLUtils and go to the macro editor there, find your character, and expand the macro set you just created.
Look for the folder "Top Bar (Control)" and open it.
You'll see something along the lines of <0702nnnn> (the brackets above aren't really the <and>, but ≺ and ≻)
The first four numbers (0702) aren't that important, and will probably be different for you. You're interested in the last four. Change the last four to use one of the unreleased spells!
It should be noted that some of these spells aren't "unreleased" but just normally unusable by players (mobs & NPCs can).
You also need to have a scroll in the same line as the unreleased spell to use it. Ie, to use Blizzaga V, you need II somewhere.
The list:
1354 Utsusemi: San
1384 Mage's Ballad III
1216 Holy II
12EA Bio V
12F8 Aspir II
1206 Cure VI
120B Curaga V
121B Dia V
1220 Banish V
1225 Diaga V
122A Banishga V
122F Protect V
1234 Shell V
126B Phalanx II
1281 Protectra V
1286 Shellra V
1294 Fire V
1299 Blizzard V
129E Aero V
12A3 Stone V
12AB Thunder V
12AD Water V
12B1 Firaga IV
12B2 Firaga V
12B6 Blizzaga IV
12B7 Blizzaga V
12BB Aeroga IV
12BC Aeroga V
12CD Stonega IV
12CE Stonega V
12C5 Thundaga IV
12C6 Thundaga V
12CA Waterga IV
12CB Waterga V
12CD Flare II
12CF Freeze II
12D1 Tornado II
12D3 Quake II
12D5 Burst II
12D7 Flood II
12D9 Gravity II
12DB Meteor II
12DE Poison III
12DF Poison IV
12E0 Poison V
12E3 Poisonga III
12E4 Poisonga IV
12E5 Poisonga V
12F6 Drain II
1242 Katon: San
1245 Hyoton: San
1348 Huton: San
134B Doton: San
134E Raiton: San
1351 Suiton: San
1357 Jubaku: San
135A hojo: San
135D Kurayami: San
1360 Dokumori: San
1363 Tonko: San
1377 Foe Rquiem VIII
1381 Army's Paeon VIII
AND here's a link where you can see how this spells looks like

:
http://www.youtube.com/watch?v=Nz_qrptnKGE
(lol yes I know this is my second post lol, I wann be sure to geta free account!

.)
oh and YES! I've tried all the 2 strategy I put on this site today, and YES THEY WORK! USE IT WISELY!