diff --git a/library/text/encoder/encoder-safe.ecf b/library/text/encoder/encoder-safe.ecf
index 1b249ddf..bff977f0 100644
--- a/library/text/encoder/encoder-safe.ecf
+++ b/library/text/encoder/encoder-safe.ecf
@@ -15,7 +15,18 @@
 		<cluster name="src" location="src\" recursive="true">
 			<file_rule>
 				<exclude>/tests$</exclude>
+				<exclude>/spec$</exclude>
 			</file_rule>
+			<cluster name="src_before_70" location="$\spec\before_70" recursive="true">
+				<condition>
+					<version type="compiler" max="7.0.8.7585"/>
+				</condition>
+			</cluster>
+			<cluster name="src_70" location="$\spec\70" recursive="true">
+				<condition>
+					<version type="compiler" min="7.0.8.7586"/>
+				</condition>
+			</cluster>
 		</cluster>
 	</target>
 	<target name="tests" extends="encoder">
diff --git a/library/text/encoder/encoder.ecf b/library/text/encoder/encoder.ecf
index de457982..0905930b 100644
--- a/library/text/encoder/encoder.ecf
+++ b/library/text/encoder/encoder.ecf
@@ -15,7 +15,18 @@
 		<cluster name="src" location="src\" recursive="true">
 			<file_rule>
 				<exclude>/tests$</exclude>
+				<exclude>/spec$</exclude>
 			</file_rule>
+			<cluster name="src_before_70" location="$\spec\before_70" recursive="true">
+				<condition>
+					<version type="compiler" max="7.0.8.7585"/>
+				</condition>
+			</cluster>
+			<cluster name="src_70" location="$\spec\70" recursive="true">
+				<condition>
+					<version type="compiler" min="7.0.8.7586"/>
+				</condition>
+			</cluster>
 		</cluster>
 	</target>
 
diff --git a/library/text/encoder/src/spec/70/utf8_url_encoder_i.e b/library/text/encoder/src/spec/70/utf8_url_encoder_i.e
new file mode 100644
index 00000000..024d3db8
--- /dev/null
+++ b/library/text/encoder/src/spec/70/utf8_url_encoder_i.e
@@ -0,0 +1,32 @@
+note
+	description : "Objects that ..."
+	author      : "$Author$"
+	date        : "$Date$"
+	revision    : "$Revision$"
+
+deferred class
+	UTF8_URL_ENCODER_I
+
+inherit
+	ANY
+
+	UNICODE_CONVERSION
+		export
+			{NONE} all
+			{ANY} is_valid_utf8
+		undefine
+			is_little_endian
+		end
+
+
+note
+	copyright: "2011-2011, Eiffel Software and others"
+	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
+	source: "[
+			Eiffel Software
+			5949 Hollister Ave., Goleta, CA 93117 USA
+			Telephone 805-685-1006, Fax 805-685-6869
+			Website http://www.eiffel.com
+			Customer support http://support.eiffel.com
+		]"
+end
diff --git a/library/text/encoder/src/spec/before_70/utf8_url_encoder_i.e b/library/text/encoder/src/spec/before_70/utf8_url_encoder_i.e
new file mode 100644
index 00000000..1b52a706
--- /dev/null
+++ b/library/text/encoder/src/spec/before_70/utf8_url_encoder_i.e
@@ -0,0 +1,73 @@
+note
+	description : "Objects that ..."
+	author      : "$Author$"
+	date        : "$Date$"
+	revision    : "$Revision$"
+
+deferred class
+	UTF8_URL_ENCODER_I
+
+inherit
+	ANY
+
+	UNICODE_CONVERSION
+		export
+			{NONE} all
+		undefine
+			is_little_endian
+		end
+
+feature -- Status report
+
+	is_valid_utf8 (a_string: STRING): BOOLEAN
+			-- Is `a_string' valid UTF-8 string?
+		require
+			a_string_not_void: a_string /= Void
+		local
+			l_nat8: NATURAL_8
+			l_code: NATURAL_32
+			i, nb, cnt: INTEGER
+		do
+			from
+				i := 1
+				nb := a_string.count
+				Result := True
+			until
+				i > nb or not Result
+			loop
+				l_nat8 := a_string.code (i).to_natural_8
+				if l_nat8 <= 127 then
+						-- Form 0xxxxxxx.
+				elseif (l_nat8 & 0xE0) = 0xC0 then
+						-- Form 110xxxxx 10xxxxxx.
+					l_code := (l_nat8 & 0x1F).to_natural_32 |<< 6
+					i := i + 1
+				elseif (l_nat8 & 0xF0) = 0xE0 then
+					-- Form 1110xxxx 10xxxxxx 10xxxxxx.
+					i := i + 2
+				elseif (l_nat8 & 0xF8) = 0xF0 then
+					-- Form 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx.
+					i := i + 3
+				elseif (l_nat8 & 0xFC) = 0xF8 then
+					-- Starts with 111110xx
+					Result := False
+				else
+					-- Starts with 1111110x
+					Result := False
+				end
+				i := i + 1
+			end
+		end
+
+
+note
+	copyright: "2011-2011, Eiffel Software and others"
+	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
+	source: "[
+			Eiffel Software
+			5949 Hollister Ave., Goleta, CA 93117 USA
+			Telephone 805-685-1006, Fax 805-685-6869
+			Website http://www.eiffel.com
+			Customer support http://support.eiffel.com
+		]"
+end
diff --git a/library/text/encoder/src/utf8_url_encoder.e b/library/text/encoder/src/utf8_url_encoder.e
index f1fbffdd..443a527f 100644
--- a/library/text/encoder/src/utf8_url_encoder.e
+++ b/library/text/encoder/src/utf8_url_encoder.e
@@ -21,12 +21,7 @@ inherit
 			decoded_string
 		end
 
-	UNICODE_CONVERSION
-		export
-			{NONE} all
-			{ANY} is_valid_utf8
-		undefine
-			is_little_endian
+	UTF8_URL_ENCODER_I
 		redefine
 			default_create
 		end
@@ -35,7 +30,7 @@ feature {NONE} -- Initialization
 
 	default_create
 		do
-			Precursor {UNICODE_CONVERSION}
+			Precursor {UTF8_URL_ENCODER_I}
 		end
 
 feature -- Access