Sometimes some Radeox macros fail to render and Radeox filter exceptions appear in the XWiki logs

10:09:33,704 [http-8080-13] WARN  filter.FilterPipe               - Filtering exception: org.radeox.filter.MarkFilter@1eb5563 
java.lang.IndexOutOfBoundsException: Index: 1, Size: 0
	at java.util.ArrayList.RangeCheck(ArrayList.java:547)
	at java.util.ArrayList.get(ArrayList.java:322)
	at org.radeox.filter.regex.RegexReplaceFilter.filter(RegexReplaceFilter.java:66)
	at org.radeox.filter.FilterPipe.filter(FilterPipe.java:169)
	at com.xpn.xwiki.render.XWikiRadeoxRenderEngine.render(XWikiRadeoxRenderEngine.java:106)
	at com.xpn.xwiki.render.XWikiRadeoxRenderer.render(XWikiRadeoxRenderer.java:72)