Thank you for contacting us on this issue.
Unfortunately, I was not able to reproduce the described behavior (with binaries from 2012_2_1009_DEV_hotfix). However, I might be missing an important part of your implementation. This is why I've attached the test project I used to reproduce the issue - please take a look at it and feel free to modify it in order to show us how to reproduce the described behavior of the RadHtmlPlaceholder.
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