how do I read an ebook on the PB4-t$% mobile phone ??

I recently bought a PB4-T45 from Ebay. Excellent phone, works well, but I did notice it had an ebook folder in it.I have tried several different ways of getting an ebook on & reading it, but none work.

I tried rendering with Rasterbook into Jpeg files.
I tried Mobipocket reader for mobiles.
I tried Wattpad.
I tried Tequilacat book reader.
I even emailed the seller in Hong Kong & they told me it uses TST files.

I checked this & tried a tst file using wordperfect.

None of the above work, HELP. HELP.