sghignone - 2006-10-11

I'm trying to assemble about 60000 seqs from a draft genome sequencing project, including sequences from fosmids, plasmids and 454 readings. Sequences are in text format. Using default settingsm, I get the error messages: "Warning: too many overlaps"  and finally "Error calculating consensus". I would like to know teh meaning of this messages and how to fix them.
Thanks in advance.