diff --git a/aegisub/libaegisub/ass/dialogue_parser.cpp b/aegisub/libaegisub/ass/dialogue_parser.cpp
index 1babd713e..921518c88 100644
--- a/aegisub/libaegisub/ass/dialogue_parser.cpp
+++ b/aegisub/libaegisub/ass/dialogue_parser.cpp
@@ -18,11 +18,12 @@
 
 #include "libaegisub/ass/dialogue_parser.h"
 
-#include "libaegisub/scoped_ptr.h"
 #include "libaegisub/spellchecker.h"
 
 #include "iconv.h"
 
+#include <boost/locale/boundary.hpp>
+
 namespace {
 
 typedef std::vector<agi::ass::DialogueToken> TokenVec;
@@ -94,70 +95,28 @@ public:
 class WordSplitter {
 	std::string const& text;
 	std::vector<DialogueToken> &tokens;
-	agi::scoped_holder<iconv_t, int(&)(iconv_t)> utf8_to_utf32;
 	size_t pos;
 
-	bool IsWordSep(int chr) {
-		static const int delims[] = {
-			0x0020, 0x0021, 0x0022, 0x0023, 0x0024, 0x0025, 0x0026, 0x0028,
-			0x0029, 0x002a, 0x002b, 0x002c, 0x002d, 0x002e, 0x002f, 0x003a,
-			0x003b, 0x003d, 0x003f, 0x0040, 0x005b, 0x005c, 0x005d, 0x005e,
-			0x005f, 0x0060, 0x007b, 0x007c, 0x007d, 0x007e, 0x00a1, 0x00a2,
-			0x00a3, 0x00a4, 0x00a5, 0x00a6, 0x00a7, 0x00a8, 0x00aa, 0x00ab,
-			0x00b0, 0x00b6, 0x00b7, 0x00ba, 0x00bb, 0x00bf, 0x02dc, 0x0e3f,
-			0x2010, 0x2013, 0x2014, 0x2015, 0x2018, 0x2019, 0x201c, 0x201d,
-			0x2020, 0x2021, 0x2022, 0x2025, 0x2026, 0x2026, 0x2030, 0x2031,
-			0x2032, 0x203b, 0x203b, 0x203d, 0x2042, 0x2044, 0x20a6, 0x20a9,
-			0x20aa, 0x20ac, 0x20ad, 0x2116, 0x2234, 0x2235, 0x2420, 0x2422,
-			0x2423, 0x2506, 0x25ca, 0x2605, 0x261e, 0x2e2e, 0x3000, 0x3001,
-			0x3002, 0x3008, 0x3009, 0x300a, 0x300b, 0x300c, 0x300d, 0x300e,
-			0x300f, 0x3010, 0x3011, 0x3014, 0x3015, 0x3016, 0x3017, 0x3018,
-			0x3019, 0x301a, 0x301b, 0x301c, 0x3030, 0x303d, 0x30fb, 0xff0a,
-			0xff5b, 0xff5d, 0xff5e
-		};
-
-		return std::binary_search(std::begin(delims), std::end(delims), chr);
-	}
-
-	int NextChar(int pos, int len, int& char_len) {
-		int chr = 0;
-		char *inptr = const_cast<char *>(&text[pos]);
-		size_t inlen = len;
-		char *outptr = (char *)&chr;
-		size_t outlen = sizeof chr;
-
-		iconv(utf8_to_utf32, &inptr, &inlen, &outptr, &outlen);
-		if (outlen != 0)
-			return 0;
-
-		char_len = len - inlen;
-		return chr;
-	}
-
 	void SwitchTo(size_t &i, int type, int len) {
-		if (tokens[i].type == type) return;
+		auto old = tokens[i];
+		tokens[i].type = type;
+		tokens[i].length = len;
 
-		if (tokens[i].length == (size_t)len)
-			tokens[i].type = type;
-		else {
-			tokens.insert(tokens.begin() + i + 1, DialogueToken(type, len));
-			tokens[i].length -= len;
+		if (old.length != (size_t)len) {
+			tokens.insert(tokens.begin() + i + 1, DialogueToken(old.type, old.length - len));
 			++i;
 		}
 	}
 
 	void SplitText(size_t &i) {
-		int chrlen = 0;
-		int len = tokens[i].length;
-		int tpos = pos;
-		for (; len > 0; tpos += chrlen, len -= chrlen) {
-			int chr = NextChar(tpos, len, chrlen);
-			if (!chr) return;
-
-			if (IsWordSep(chr))
-				SwitchTo(i, dt::TEXT, len);
-			else
+		using namespace boost::locale::boundary;
+		ssegment_index map(word, text.begin() + pos, text.begin() + pos + tokens[i].length);
+		for (auto const& segment : map) {
+			int len = distance(begin(segment), end(segment));
+			if (segment.rule() & word_letters)
 				SwitchTo(i, dt::WORD, len);
+			else
+				SwitchTo(i, dt::TEXT, len);
 		}
 	}
 
@@ -165,7 +124,6 @@ public:
 	WordSplitter(std::string const& text, std::vector<DialogueToken> &tokens)
 	: text(text)
 	, tokens(tokens)
-	, utf8_to_utf32(iconv_open("utf-32le", "utf-8"), iconv_close)
 	, pos(0)
 	{ }
 
@@ -175,7 +133,7 @@ public:
 		for (size_t i = 0; i < tokens.size(); ++i) {
 			size_t len = tokens[i].length;
 			if (tokens[i].type == dt::TEXT)
-					SplitText(i);
+				SplitText(i);
 			pos += len;
 		}
 	}
diff --git a/aegisub/tests/tests/word_split.cpp b/aegisub/tests/tests/word_split.cpp
index 3ffb3a3be..4c19de763 100644
--- a/aegisub/tests/tests/word_split.cpp
+++ b/aegisub/tests/tests/word_split.cpp
@@ -126,10 +126,11 @@ TEST(lagi_word_split, unclosed_ovr) {
 	};
 
 	SplitWords(text, tokens);
-	ASSERT_EQ(3u, tokens.size());
+	ASSERT_EQ(4u, tokens.size());
 	EXPECT_EQ(dt::WORD, tokens[0].type);
 	EXPECT_EQ(dt::TEXT, tokens[1].type);
-	EXPECT_EQ(dt::WORD, tokens[2].type);
+	EXPECT_EQ(dt::TEXT, tokens[2].type);
+	EXPECT_EQ(dt::WORD, tokens[3].type);
 
 	text = "{";
 	tokens.clear();
@@ -140,3 +141,22 @@ TEST(lagi_word_split, unclosed_ovr) {
 	EXPECT_EQ(dt::TEXT, tokens[0].type);
 }
 
+TEST(lagi_word_split, several_words) {
+	std::string text = "a bb ccc dd e";
+	std::vector<DialogueToken> tokens = {
+		{dt::TEXT, 13},
+	};
+
+	SplitWords(text, tokens);
+	ASSERT_EQ(9u, tokens.size());
+	EXPECT_EQ(1, tokens[0].length);
+	EXPECT_EQ(1, tokens[1].length);
+	EXPECT_EQ(2, tokens[2].length);
+	EXPECT_EQ(1, tokens[3].length);
+	EXPECT_EQ(3, tokens[4].length);
+	EXPECT_EQ(1, tokens[5].length);
+	EXPECT_EQ(2, tokens[6].length);
+	EXPECT_EQ(1, tokens[7].length);
+	EXPECT_EQ(1, tokens[8].length);
+}
+