UnicodeDecodeError: 'ascii' codec can't decode byte 0xe6 in position 74: ordinal not

[caixia song]

I use the ubuntu10.04, and when i compile a package which is in ROS, the error occurs as following:
File "/usr/lib/python2.6/logging/handlers.py", line 76, in emit
if self.shouldRoll over(record):
File "/usr/lib/python2.6/logging/handlers.py", line 149, in shouldRollover
msg = "%s\n" % self.format(rec ord)
File "/usr/lib/python2.6/logging/__init__.py", line 648, in format
return fmt.format(reco rd)
File "/usr/lib/python2.6/logging/__init__.py", line 436, in format
record.message = record.getMessa ge()
File "/usr/lib/python2.6/logging/__init__.py", line 306, in getMessage
msg = msg % self.args
UnicodeDecodeEr ror: 'ascii' codec can't decode byte 0xe6 in position 74: ordinal not in range(128)

I also do the following commands and it shows the message:
rct@rct-desktop:~$ python
Python 2.6.5 (r265:79063, Apr 16 2010, 13:09:56)
[GCC 4.4.3] on linux2
Type "help", "copyright" , "credits" or "license" for more information.
>>> import locale
>>> locale.getlocal e()
(None, None)
>>> locale.setlocal e(locale.LC_ALL ,"")
'zh_HK.utf8'
>>> locale.getlocal e()
('zh_HK', 'UTF8')
>>>