Fix regression caused by the fix for AHX 78, thanks to Dominic for his test case

Author: jfarcand

pom.xml

@@ -151,6 +151,19 @@
             </exclusions>
         </dependency>
 
+		<dependency>
+			<groupId>commons-io</groupId>
+			<artifactId>commons-io</artifactId>
+			<version>2.0.1</version>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>commons-fileupload</groupId>
+			<artifactId>commons-fileupload</artifactId>
+			<version>1.2.2</version>
+			<scope>test</scope>
+		</dependency>
+
         <!-- Optional Apache Http Client -->
         <dependency>
             <groupId>commons-httpclient</groupId>

src/main/java/com/ning/http/client/StringPart.java

@@ -20,12 +20,20 @@
  * A string multipart part.
  */
 public class StringPart implements Part {
-    private String name;
-    private String value;
+    private final String name;
+    private final String value;
+    private final String charset;
+
+    public StringPart(String name, String value, String charset) {
+        this.name = name;
+        this.value = value;
+        this.charset = charset;
+    }
 
     public StringPart(String name, String value) {
         this.name = name;
         this.value = value;
+        this.charset = "UTF-8";
     }
 
     public String getName() {
@@ -35,4 +43,9 @@ public String getName() {
     public String getValue() {
         return value;
     }
+
+    public String getCharset() {
+        return charset;
+    }
+
 }

src/main/java/com/ning/http/util/AsyncHttpProviderUtils.java

@@ -214,7 +214,7 @@ public final static MultipartRequestEntity createMultipartRequestEntity(List<Par
             } else if (part instanceof StringPart) {
                 parts[i] = new com.ning.http.multipart.StringPart(part.getName(),
                         ((StringPart) part).getValue(),
-                        "UTF-8");
+                        ((StringPart) part).getCharset());
             } else if (part instanceof FilePart) {
                 parts[i] = new com.ning.http.multipart.FilePart(part.getName(),
                         ((FilePart) part).getFile(),