4200's venting

[craigosh]

Got some 1 run only 4200's off ebay and when i cycled them last night they vented leaving some nice stains on the paper below them... Do i need to worry about it?

They didnt do it this morning when i discharged them a little then repeaked them and the temp gun says they are reaching about 57C each cell which i read on SMC's site is about right..

Charging them on an eagle CDC at 6amps and the peak detect is 5mv (per cell)