HTseq Error occured:'need more than 10 values to unpack' in line of sam file

[Tuinhof]

Dear members of SEQanwers,

I have a HTseq error, witch is not known by this forum.

Error occured in line 28113765 of file /mnt/scrap_disk_1/Eric_cold_pilot/7/accepted_hits_sorted.sam.
Error: ('need more than 10 values to unpack', 'line 28113765 of file /mnt/scrap_disk_1/Eric_cold_pilot/7/accepted_hits_sorted.sam')
[Exception type: ValueError, raised in _HTSeq.pyx:1252]

This is the HTseq command line:

python -m HTSeq.scripts.count -s no -t exon -i gene_id -m intersection-strict /mnt/scrap_disk_1/Eric_cold_pilot/7/accepted_hits_sorted.sam Anguilla_anguilla_genome_v1_09_nov_10.gff > 7.tsv;

The strange thing is that the previous samples 1-6 are running fine.
But there is something wrong with the SAM file after sorting (with samtools)???
Does anyone recognize this error?
Any suggestions how to solve this error?

Thanks in advance!