diff --git a/jenkins-client/src/main/java/com/offbytwo/jenkins/client/FormBinaryField.java b/jenkins-client/src/main/java/com/offbytwo/jenkins/client/FormBinaryField.java
new file mode 100644
index 00000000..72d25b7e
--- /dev/null
+++ b/jenkins-client/src/main/java/com/offbytwo/jenkins/client/FormBinaryField.java
@@ -0,0 +1,25 @@
+package com.offbytwo.jenkins.client;
+
+public class FormBinaryField {
+  private String fileName;
+  private String contentType;
+  private byte[] content;
+
+  public FormBinaryField(String fileName, String contentType, byte[] content) {
+    this.fileName = fileName;
+    this.contentType = contentType;
+    this.content = content;
+  }
+
+  public String getFileName() {
+    return fileName;
+  }
+
+  public String getContentType() {
+    return contentType;
+  }
+
+  public byte[] getContent() {
+    return content;
+  }
+}
diff --git a/jenkins-client/src/main/java/com/offbytwo/jenkins/client/JenkinsHttpClient.java b/jenkins-client/src/main/java/com/offbytwo/jenkins/client/JenkinsHttpClient.java
index c2eaf3b1..a1fe527b 100755
--- a/jenkins-client/src/main/java/com/offbytwo/jenkins/client/JenkinsHttpClient.java
+++ b/jenkins-client/src/main/java/com/offbytwo/jenkins/client/JenkinsHttpClient.java
@@ -30,6 +30,7 @@
 import org.apache.http.client.methods.HttpRequestBase;
 import org.apache.http.entity.ContentType;
 import org.apache.http.entity.StringEntity;
+import org.apache.http.entity.mime.HttpMultipartMode;
 import org.apache.http.entity.mime.MultipartEntityBuilder;
 import org.apache.http.impl.auth.BasicScheme;
 import org.apache.http.impl.client.BasicCredentialsProvider;
@@ -421,6 +422,7 @@ public void post_multipart_form_json(String path, Map<String, Object> data, bool
         HttpPost request;
         if (data != null) {
             MultipartEntityBuilder builder = MultipartEntityBuilder.create();
+            builder.setMode(HttpMultipartMode.BROWSER_COMPATIBLE);
             for (Map.Entry<String, Object> entry : data.entrySet()) {
                 String fieldName = entry.getKey();
                 Object fieldValue = entry.getValue();
@@ -428,12 +430,15 @@ public void post_multipart_form_json(String path, Map<String, Object> data, bool
                     builder.addTextBody(fieldName, (String) fieldValue);
                 } else if (fieldValue instanceof byte[]) {
                     builder.addBinaryBody(fieldName, (byte[]) fieldValue);
+                } else if (fieldValue instanceof FormBinaryField) {
+                    FormBinaryField binaryField = (FormBinaryField) fieldValue;
+                    builder.addBinaryBody(fieldName, binaryField.getContent(), ContentType.create(binaryField.getContentType()), binaryField.getFileName());
                 } else if (fieldValue instanceof File) {
                     builder.addBinaryBody(fieldName, (File) fieldValue);
                 } else if (fieldValue instanceof InputStream) {
                     builder.addBinaryBody(fieldName, (InputStream) fieldValue);
                 } else {
-                    throw new IllegalArgumentException("type of field " + fieldName + " is not String, byte[], File or InputStream");
+                    builder.addTextBody(fieldName, JSONObject.fromObject(fieldValue).toString());
                 }
             }
             request = new HttpPost(noapi(path));
diff --git a/jenkins-client/src/main/java/com/offbytwo/jenkins/model/credentials/AppleDeveloperProfileCredential.java b/jenkins-client/src/main/java/com/offbytwo/jenkins/model/credentials/AppleDeveloperProfileCredential.java
index 8b84ab8a..a1f30dd5 100644
--- a/jenkins-client/src/main/java/com/offbytwo/jenkins/model/credentials/AppleDeveloperProfileCredential.java
+++ b/jenkins-client/src/main/java/com/offbytwo/jenkins/model/credentials/AppleDeveloperProfileCredential.java
@@ -1,5 +1,6 @@
 package com.offbytwo.jenkins.model.credentials;
 
+import com.offbytwo.jenkins.client.FormBinaryField;
 import net.sf.json.JSONObject;
 
 import java.util.HashMap;
@@ -17,6 +18,9 @@ public class AppleDeveloperProfileCredential extends Credential {
   private static final String FILE_ZERO_FIELD_NAME = "file0";
   private static final String FILE_ONE_FIELD_NAME = "file1";
 
+  private static final String DEFAULT_DEV_PROFILE_NAME = "developerProfile.zip";
+  private static final String DEFAULT_DEV_PROFULE_CONTENT_TYPE = "application/zip";
+
   private String password;
   private byte[] developerProfileContent;
 
@@ -72,14 +76,14 @@ public Map<String, Object> dataForCreate() {
     jsonData.put("credentials", credentialMap);
 
     Map<String, Object> formFields = new HashMap<String, Object>();
-    formFields.put(FILE_ZERO_FIELD_NAME, this.getDeveloperProfileContent());
+    formFields.put(FILE_ZERO_FIELD_NAME, new FormBinaryField(DEFAULT_DEV_PROFILE_NAME, DEFAULT_DEV_PROFULE_CONTENT_TYPE, this.getDeveloperProfileContent()));
     formFields.put("_.scope", SCOPE_GLOBAL);
     formFields.put("_.password", this.getPassword());
     formFields.put("_.id", this.getId());
     formFields.put("_.description", this.getDescription());
     formFields.put("stapler-class", BASECLASS);
     formFields.put("$class", BASECLASS);
-    formFields.put("json", JSONObject.fromObject(jsonData).toString());
+    formFields.put("json", jsonData);
     return formFields;
   }
 
@@ -95,7 +99,7 @@ public Map<String, Object> dataForUpdate() {
 
 
     Map<String, Object> formFields = new HashMap<String, Object>();
-    formFields.put(FILE_ONE_FIELD_NAME, this.getDeveloperProfileContent());
+    formFields.put(FILE_ONE_FIELD_NAME, new FormBinaryField(DEFAULT_DEV_PROFILE_NAME, DEFAULT_DEV_PROFULE_CONTENT_TYPE, this.getDeveloperProfileContent()));
     formFields.put("_.", "on");
     formFields.put("_.password", this.getPassword());
     formFields.put("_.id", this.getId());