Show_posts="true" not working with custom post

I am using the following code to create a mashup

[map query="post_type=post_cpt" overlay="true" zoom="4" show_posts="true" overlay="true" map_type="ROADMAP" show_images="false" height="300" width="100%" disable_scroll="true"]

where post_cpt is my custom post type.

I was expecting to click on the marker and be taken to the post, but all I get is the address.

I have changed

query="post_type=post_cpt"

to
query="all"

to see if that was the error with no luck, Any suggestions would be very helpful!