diff --git a/src/data/mime_db/application/xhtml+xml b/src/data/mime_db/application/xhtml+xml
index d6d4418998..8e2a40b620 100644
--- a/src/data/mime_db/application/xhtml+xml
+++ b/src/data/mime_db/application/xhtml+xml
@@ -4,7 +4,9 @@ resource(0, "BEOS:TYPE") #'MIMS' "application/x-vnd.Be-meta-mime";
 resource(1, "META:TYPE") "application/xhtml+xml";
 
 resource(2, "META:SNIFF_RULE") #'CSTR' array {
-	"0.60  [0](\"<?xml\"|\"\\376\\377\\000<\\000?\\000x\\000m\\000l\") [0:128](\"<!DOCTYPE html\"|\"\\000<\\000!\\000D\\000O\\000C\\000T\\000Y\\000P\\000E\\000 \\000h\\000t\\000m\\000l\")"
+	"0.60 [0:512](\"<html xmlns\" | "
+	"\"<\\000h\\000t\\000m\\000l\\000 \\000x\\000m\\000l\\000n\\000s\" | "
+	"\"-//W3C//DTD XHTML\")"
 };
 
 resource(3, "META:S:DESC") #'MSDC' "XHTML file";
diff --git a/src/data/mime_db/multipart/related b/src/data/mime_db/multipart/related
index abd66320a7..70bbfa408c 100644
--- a/src/data/mime_db/multipart/related
+++ b/src/data/mime_db/multipart/related
@@ -4,7 +4,7 @@ resource(0, "BEOS:TYPE") #'MIMS' "application/x-vnd.Be-meta-mime";
 resource(1, "META:TYPE") "multipart/related";
 
 resource(2, "META:SNIFF_RULE") #'CSTR' array {
-	"0.40  [0:256]( -i \"Content-Type: multipart-related;\")"
+	"0.50  [0:256]( -i \"Content-Type: multipart-related;\")"
 };
 
 resource(3, "META:S:DESC") #'MSDC' "MHTML file";
diff --git a/src/data/mime_db/text/html b/src/data/mime_db/text/html
index 8e6ecbbd7d..042a031354 100644
--- a/src/data/mime_db/text/html
+++ b/src/data/mime_db/text/html
@@ -4,7 +4,7 @@ resource(0, "BEOS:TYPE") #'MIMS' "application/x-vnd.Be-meta-mime";
 resource(1, "META:TYPE") "text/html";
 
 resource(2, "META:SNIFF_RULE") #'CSTR' array {
-	"0.40  [0:256]( -i \"<HTML\" | \"<HEAD\" | \"<TITLE\" | \"<BODY\" | "
+	"0.40  [0:512]( -i \"<HTML\" | \"<HEAD\" | \"<TITLE\" | \"<BODY\" | "
 	"\"<TABLE\" | \"<META\" | \"<CENTER\" | \"<!DOCTYPE HTML\" | \"<SCRIPT\" | "
 	"\"<STYLE\" | \"<A HREF\" )"
 };
