How can I use internal sd for ClockworkMod on a Motorola Defy?
It means that the recovery does not mount the internal memory by default, and you need to do so manually.

On your PC download and install Android SDK tools which gets you the ADB utility.  Reboot your phone in Recovery mode and connect it to your PC via USB cable.  Install the drivers if prompted (use drivers that ship with SDK tools under the \sdk\extras\google\usb_driver\ subfolder.)  Now run Command Prompt, navigate to where you installed the tools (e.g. cd C:\Android SDK\sdk\platform-tools\ ) and issue the following command:


  adb shell mount /data


You now should be able to use the "adb push" command in Windows Command Prompt to copy files from your PC to the phone using the following syntax:


  adb push [path-to-file-on-your-pc] /data/


After the copy completes, you should be able to find the copied file in the Recovery's file browser.