ASCII dump Custom Column

I am trying to set up a column to display an ASCII dump. The 'Packet Bytes' pane shows this information, but I cannot find a way to create a custom column to display the same information. When I use the data.data filter, the hex dump is displayed. When I use the data.text filter, a strange string is displayed instead of the ASCII dump that I was expecting. For example, I have a payload (encapsulated in a TCP frame):

3c0b64c8ff4cd802026d67fa3e

I can display this hex dump in a custom column using a data.data filter, but when I use data.text, this is displayed:

<\vd\357\277\275\357\277\275L\357\277\275\002\002mg\357\277\275>

When I use data.text, I would like this to be displayed (this is displayed in the Packet Bytes pane):

<.d..L...mg.>

I don't know where Wireshark is coming up with the information that is displayed using the data.text filter. Is there any way to display this hex payload as ASCII?

I am running Wireshark 1.12.4 on Windows 7.