Hack open a cell for which you don`t have a power adaptor or if the jack is damaged. Use any other mobile phone power adaptor and give your deciesed mobile a second chance.
Step 1: Hack Open Your Cell.
Carefully open your phone. Mine had torx screws, which I later replaced with philips. Be careful on not to lose any component, like mics, speakers, vibrators, SIM, etc. Locate the power jack. Mine has one that serves as power and handsfree. Other mobiles have separate ones. So it will be easier to locate them. carefully solder off the old jack.
Step 2: Solder Wires
Carefully solder wires to the pads. Mine had three. Yours probably two. The outer countour is generally NEGATIVE. So look closely at the pads and tracks.
Step 3: Use a Small Enough Jack.
Use a small enough jack. I used the type commonly found on Desktop PCs. Use hot melt glue to firmly attach it to the circuit board and/or case.
Step 4: Connect the Power Adaptor
Solder the other gender connector to your 'saved from the junk' power adaptor. Make sure that the OUTPUT voltage of this one is not grater than 5 Vdc. Most phones use this rating, so it is almost universal on all brands. I used a Samsung power adaptor with my Sendo 251 mobile.
Step 5: Check If the Power Cord Icon or Charging in Progress Is Shown
Now your mobile must have had detected power being supplied. Don't worry if you reverse the polarity, 5 Vdc is hardly going to damage your cell. Mine only went off. If you do damage it, well don't mind it, since you were already think on dumping it! ;-)