Use diahmap

For an object to be identified by the script, you have to group it with
a Text that will act as an identifier.

Explanation of list values:
Value 1: Object type - This is the name that Dia uses to identify an
    object. To find out what this string is select the object in dia and
    the name will be written in the status bar(Selected 'Cisco - PC').
Value 2: Text string - A string of text that is grouped with the object.
    Just add a piece of Text, select it with the object and group them.
Value 3: Link - This is the location that href for this object will
    point to. These can be modified by adding a prefix or a suffix.
Value 4: Link text(optional) - This value determines if the script will
    add a map area for the Text too. Default is 0;

Example list:
Cisco - PC;    you;      you.html;     1
Cisco - Cloud; internet; internet.html

This value offsets the map and is interpreted in pixels. Example: 10,-5

Usage in DokuWiki:
You can download a slightly modified version of the image_map plugin
here. You can also install it through the plugin manager. The only
difference is that the original plugin leaves all the links under the
image, which is a problem for me, because all I wanted was a simple
image with a map. The syntax is explained on the plugin wiki page. Just
copy the generated code and edit the first line to include your image.

Example of a map generated using the example list and this dia file.
example you you internet
Coded by Tin Benjamin Matuka