I have been able to duplicate this behaviour and I'll be darned if I can explain it. Yes the menu is enabled, yes the Select all (Ctrl+A) is enabled but Ctrl+A does NOT select the text in the EditBox, although it will select the text in TextBox in the same grid.
Maybe you can convince your user to use Shift-End to select text? That appears to work in both although it only selects from cursor to end of field.
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John Koziol, ex-MVP, ex-MS, ex-FoxTeam. Just call me "X"
"When the going gets weird, the weird turn pro" - Hunter Thompson (Gonzo) RIP 2/19/05