Pressing Escape to close KMail About dialog causes segfault if QT_ACCESSIBILITY=1 is in environment

Preparation:
1.Do these things: http://userbase.kde.org/Accessibility/Getting_Started

Steps to reproduce:
1. Launch KMail in accessible environment (see Getting Started)
2. Help menu -> About KMail
3. Wait for the dialog to appear, then press Escape

I reliably get a segfault, even if an AT is not listening. (See attached.)