Characters such as apostrophes and smart quotes turning into boxes or question marks

We recently upgraded from CF5 to CF7 and are having a problem with previously saved text that no longer displays correctly. Some characters (apparently, non-ASCII characters such as curly apostrophes and smart quotes) are rendering as boxes or question marks. We recently upgraded to Oracle 10g from Oracle 8i, but this problem appears to be independent of the database that the text is stored in. Here is sample code that will illustrate the problem:

<CFSET string1="Department’s">
<CFSET string2="hey—there">

<CFOUTPUT>
string1 is #string1#
<BR>
string2 is #string2#
</CFOUTPUT>

output looks like this:

string1 is Department?s
string2 is hey?there

These are rendered as boxes when viewed in Internet Explorer. (They show up as question marks when I copy and paste them here.)

The Demoronize UDF helps *some* of the time, but this is still happening with a lot of text, especially text that gets pasted from a website into a form, then saved to a database. Does anybody have a solution for this? This is breaking my applications and is incredibly annoying. I'd like to either replace the problematic characters at the time they are displayed, or replace them when they are input in the database in the first place (and go back and update all the previously saved data to replace the problematic characters with plain text equivalents).

Any suggestions appreciated.