Attachement as html - email

Question

I want to create a support button in a Java application which should send an e-mail to the support e-mail address with some attachments.
The problem is that the mail server is variable for different users, therefore I cannot use the JavaMail API because I cannot set the server. I am left with the basic mailTo feature, with the following parameters:
mailTo:email#domain.com?subject=TEST%20SUBJECT&body=TEST%20BODY
This command will open the default e-mail service(Lotus Notes) on the user's PC with the content of the e-mail already formatted.
I also want to add an attachment to the e-mail, but since mailTo does not allow it, the only option left is to add it from the body of the e-mail.
I manually added an attachement to the e-mail body and looking at it's properties I do not have much options to work with:
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://camel.apache.org/schema/spring http://camel.apache.org/schema/spring/camel-spring.xsd">
<camelContext xmlns="http://camel.apache.org/schema/spring">
<route>
<from uri="timer://simpleTimer?period=1000" />
<setBody>
<simple>
<Hello from timer at $ header.firedTime } />
</simple>
</setBody>
<to uri="stream:out" />
</route>
</camelContext>
</beans
I am not familiar with web-development, so I thought, are there any tags or is it possible to add some web-scripts to the e-mail body to automatically load the attachement from an absolute path?
I am expecting to be something like:
mailTo:email#domain.com?subject=TEST%20SUBJECT&body=<some tag which adds an attachement>
or
mailTo:email#domain.com?subject=TEST%20SUBJECT&body=some_web_script