MailScanner (Batch: Found invalid qf queue file..)

[Harry Hanson]

all fo the sudden started seeing these types of errors..

Dec  9 18:10:05 mx01 MailScanner[96276]: Batch: Found invalid qf queue file
for message hB926xWh038695
Dec  9 18:10:05 mx01 MailScanner[96276]: Batch: Found invalid qf queue file
for message hB927GWh038481
Dec  9 18:10:05 mx01 MailScanner[96543]: Batch: Found invalid qf queue file
for message hB926xWh038695
Dec  9 18:10:05 mx01 MailScanner[96543]: Batch: Found invalid qf queue file
for message hB927GWh038481
Dec  9 18:10:05 mx01 MailScanner[96416]: Virus and Content Scanning:
Starting
Dec  9 18:10:05 mx01 MailScanner[96160]: Batch: Found invalid qf queue file
for message hB926xWh038695
Dec  9 18:10:05 mx01 MailScanner[96160]: Batch: Found invalid qf queue file
for message hB927GWh038481
Dec  9 18:10:06 mx01 MailScanner[96696]: Batch: Found invalid qf queue file
for message hB926xWh038695
Dec  9 18:10:06 mx01 MailScanner[96696]: Batch: Found invalid qf queue file
for message hB927GWh038481

any ideas what might be causing these, or why?

thanks.