Yes, we have also encountered this, and other issues, as a result of loading this version of the client. Although I must add that the problem was intermittent and was dependent upon the hardware. For example, we standardize with IBM hardware, I downloaded and tested the client before deploying and I had no problems (my system is about 1 year old). On newer systems we experienced this problem and the postfix did not fix the problem it created other problems.
Use version 4.9 or, in some cases we have had to revert back to 4.83sp2 with XP users. Isn't technology great!