R.app appending newline at end of command

Hi,

Recently, R.app (2.7.2 on Leopard 10.5.4) has begun to append newlines 
at the end of commands, so that if I press the up key, the newline gets 
reproduced again. I've been running 2.7.2 since it came out but this 
behaviour is recent (past couple of days):

 > ls()
character(0)
[press up and enter]
 > ls()
character(0)
 >
[press up and enter]
 > ls()
character(0)
 >
 >
[press up and enter]
 > ls()
character(0)
 >
 >
 >


 > sessionInfo()
R version 2.7.2 (2008-08-25)
i386-apple-darwin8.11.1

locale:
en_AU.UTF-8/en_AU.UTF-8/C/C/en_AU.UTF-8/en_AU.UTF-8

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base


Any idea what could be causing this?

Thanks,
Gad

Gad Abraham
Dept. CSSE and NICTA
The University of Melbourne
Parkville 3010, Victoria, Australia
email: gabraham at csse.unimelb.edu.au
web: http://www.csse.unimelb.edu.au/~gabraham