WARNING: do this at your own risk, lipo batteries can rupture and cause a significant fire hazard, especially if they have been over-discharged or over-charged.
As you can see in this video, it is possible to save a lipo battery that your charger refuses to charge -- so long as you are *very* careful.
Remember, a battery recovered in this way should always be treated with caution afterwards but providing sufficient care is taken, a rescued battery can continue to provide many more cycles of use.