It's not uncommon for group 49 batteries to have the caps on the cells. Being sealed however doesn't mean you won't get spillage from a charge.

I took out and charged my sealed group 49 Die Hard two nights ago and noticed last night that it was sitting in a huge puddle of battery acid. I wiped it up with an old towel (that will soon dissolve into lint). The epoxy garage floor is now very clean in that spot now.

As for jumping with cables, you only get a partial connection through the jumper cables. To really work well, you need to clamp on cables from battery to battery, which isn't very practicable.

__________________
Michael LaFleur

'05 E320 CDI - 86,000 miles
'86 300SDL - 360,000 miles
'85 300SD - 150,000 miles (sold)
'89 190D - 120,000 miles (sold)
'85 300SD - 317,000 miles (sold)
'98 ML320 - 270,000 miles (sold)
'75 300D - 170,000 miles (sold)
'83 Harley Davidson FLTC (Broken again) :-(
'61 Plymouth Valiant - 60k mikes
2004 Papillon (Oliver)
2005 Tzitzu (Griffon)
2009 Welsh Corgi (Buba)