Scenario 1: Client wants the image map in their e-catalog to open the end user's email client for them to compose an email to a specific sender.
To configure an image map to launch the end user's email client, change the image map href field to be some variant of this syntax:
Scenario 2: Client wants the image map in their e-catalog to automatically send a default email message to a specific sender.
Then, it is a matter of configuring the image map to call the appropriate function on click. So, if you designed a function named SendMail(emailaddress), which references the email address to send to in the function call, you could configure the image map href field to contain the desired email addresses. Then, you could set up the href template for the e-catalog page to call the function and pass in the email address from the href field of the image map by setting the href template, like so:
Provided the function then is configured to correctly trigger an email from the web servers email server, then this method works as desired.