diff --git a/share/mk/doc.docbook.mk b/share/mk/doc.docbook.mk
index 0876c79115..d999ae9c0d 100644
--- a/share/mk/doc.docbook.mk
+++ b/share/mk/doc.docbook.mk
@@ -257,7 +257,11 @@ TOUCH?=		/usr/bin/touch
 XARGS?=		/usr/bin/xargs
 
 GROFF?=		groff
-TIDYOPTS?=	-wrap 90 -m -f /dev/null -asxml ${TIDYFLAGS}
+.if empty(LANGCODE:S/./ . /g:MISO8859-1)
+TIDYOPTS?=	-wrap 90 -m -raw -preserve -f /dev/null -asxml ${TIDYFLAGS}
+.else
+TIDYOPTS?=	-wrap 90 -m -f /dev/null -asxml ${TIDYFLAGS
+.endif
 HTML2TXT?=	${PREFIX}/bin/links
 HTML2TXTOPTS?=	-dump -width 72 ${HTML2TXTFLAGS}
 HTML2PDB?=	${PREFIX}/bin/iSiloBSD