Please forgive if this has been addressed...
I have both KM 1.5.3 and 1.1.6 (in seperate folders, of course) because 1.1.6 actually works better for me in some ways.
So, I noticed....under Tools/User Agent, 1.1.6 offers a version of IE but 1.5.3 does not. Why is that? Is it because of a change to IE?
I think you can fix it. Try these steps.
Open 1.1.6 and use TOOLS - USER AGENT to set to IE.
Use HELP - ABOUT K-MELEON to open the help page.
Copy the user agent string to the clipboard.
Close 1.1.6 and open 1.5.3
Use TOOLS - USER AGENT and select custom.
Copy the IE string from the clipboard and click OK.
Use HELP - ABOUT K-MELEON to open the help page.
You should see the IE user agent string.