redisplay-problem - border around frame

After updating from 21.5.9 to the latest CVS, I have a fairly annoying white, inconsistent, thin border around my XEmacs-frame. See at http://buug.mind.de/~khaberz/xemacsborder.png C-l will consistently get rid of it until I do something in the frame again. PLease let me know if I can provide more info. Thanks! ===================== uname -a: FreeBSD zaphod.khaberz.net 4.9-STABLE FreeBSD 4.9-STABLE #0: Sat Nov 1 18:11:56 CET 2003 khaberz＠zaphod.khaberz.net:/usr/obj/usr/src/sys/ZAPHOD i386 ./configure '--error-checking=none' '--with-toolbars=no' '--with-mule=yes' '--prefix=/usr/local/xem acs' XEmacs 21.5-b16 "celeriac" configured for `i386-unknown-freebsd4.9'. Compilation / Installation: Source code location: /usr/home/khaberz/sources/xemacs/xemacs-21.5 Installation prefix: /usr/local/xemacs Runtime library search path: /usr/X11R6/lib Operating system description file: `s/freebsd.h' Machine description file: `m/intel386.h' Compiler: gcc -Wall -Wno-switch -Winline -Wmissing-prototypes -Wsign-comp are -Wundef -Wstrict-prototypes -Wshadow -Wmissing-declarations -Wpointer-arith -g -O3 Relocating allocator for buffers: yes GNU version of malloc: yes Linking with `-z nocombreloc'. - Consider configuring with --pdump. Window System: Compiling in support for the X window system: - X Windows headers location: /usr/X11R6/include - X Windows libraries location: /usr/X11R6/lib - Handling WM_COMMAND properly. Using Lucid menubars. Using Lucid scrollbars. Using Motif dialog boxes. Using Motif native widgets. TTY: Compiling in support for ncurses. Images: Compiling in support for GIF images (builtin). Compiling in support for XPM images. WARNING: ----------------------------------------------------------- WARNING: Compiling without PNG image support. WARNING: You should strongly consider installing the PNG libraries. WARNING: Otherwise certain images and glyphs may not display. WARNING: (a copy may be found in ftp://ftp.xemacs.org/pub/xemacs/aux) WARNING: ----------------------------------------------------------- Sound: Compiling in support for sound (native). Databases: Compiling in support for DBM. Internationalization: Compiling in support for Mule (multi-lingual Emacs). Compiling in support for XIM (X11R5+ I18N input method). - Using Motif to provide XIM support. Mail: Compiling in support for "flock" mail spool file locking method. Other Features: Inhibiting IPv6 canonicalization at startup. Compiling in support for dynamic shared object modules. Compiling in support for extra debugging code.