fake:

package/rene/ffmpeg/ffmpeg.conf

@@ -23,7 +23,7 @@
 # fill options the configure does not attempt to detect ...
 pkginstalled lame && var_append extraconfopt " " "--enable-mp3lame"
 pkginstalled ogg-vorbis && var_append extraconfopt " " "--enable-vorbis" 
-pkginstalled a52dec && var_append extraconfopt " " "--enable-a52 --enable-gpl"
+pkginstalled a52dec && var_append extraconfopt " " "--enable-a52"
 
 var_append confopt " " "--enable-shared --enable-pp --enable-gpl"