This article helped me today:
Using
The culprit turned out to be the encoding of the HTML mail - the aforementioned mail user agents were detecting one character set and re-formatting the source, resulting in characters being dropped or added to the source.
The fix was to use
2<cfmail from="#from_string#" to="#strEmailTo#" subject="#strMsgSubject#" type="html">
3 <!--- headers and attachments --->
4 <cfmailparam name="List-Unsubscribe" value="<mailto:abuse@baconsavers.com>,<#strUnsubLink#?#strClientInfoHash#>">
5 <!--- plain version of message --->
6 <cfmailpart type="text/plain" charset="utf-8">#strTextOnlyMsg#</cfmailpart>
7 <!--- HTML version of message --->
8 <cfmailpart type="text/html" charset="utf-8">#strHTMLMsg#</cfmailpart>
9</cfmail>
Team Ravenglass