cat'ing all vcf files together should work
BEGIN:VCARD VERSION:2.1 UID:662 REV:2011-05-14T10:21:32Z TEL;CELL;VOICE:123456789 N:;Alejandra;;; EMAIL:fakeemail@gmail.com END:VCARD BEGIN:VCARD VERSION:2.1 UID:620 REV:2011-01-21T16:18:53Z TEL;CELL;VOICE:123456789 N:;Ana;;; END:VCARD BEGIN:VCARD VERSION:2.1 UID:603 REV:2011-01-22T14:27:53Z TEL;CELL;VOICE:123456789 N:;Antonio;;; END:VCARD And so on...