Learned Words not Correcting Spelling Error Indication.

Scrivener v Beta 1.6
OS Windows XP sp3
Computer Dell Precision PWS380 Pentium D 2.80 Ghz
3.5 Gb RAM

Problem description:
Right-clicking on an unknown word in reasearch text and selecting “Learn Spelling” does not remove the red-underline indicating a misspelt word. The word is added to the Personal Word List. Switching to another part of Scrivener does not cause the highlight to disappear. Re-opening Scrivener causes the spelling higlighting to work correctly.

Expected behaviour:
Once the word has been added to the Personal Word List the highlight should immediately disappear without requiring a restart.

Minimum steps to reproduce.
Enter some text with some unknown words into a new reasearch item.
Right click on a misspelt word.
Select “Learn Spelling”
Observe that the red highlight does not disappear.