fixed tests for phantomjs < 1.6

-Subproject commit dd54a24e01c379ad5b34dfb2ec11323a95a7e25f
+Subproject commit 8ef6a7b312c799466acf3691de0a59d7f48a4c29

@@ -221,6 +221,9 @@ Casper.prototype.base64encode = function base64encode(url, method, data) {
  */
 Casper.prototype.capture = function capture(targetFile, clipRect) {
     "use strict";
+    if (!this.started) {
+        throw new CasperError("Casper not started, can't capture()");
+    }
     var previousClipRect;
     targetFile = fs.absolute(targetFile);
     if (clipRect) {
@@ -258,6 +261,13 @@ Casper.prototype.capture = function capture(targetFile, clipRect) {
  */
 Casper.prototype.captureBase64 = function captureBase64(format, area) {
     "use strict";
+    if (!this.started) {
+        throw new CasperError("Casper not started, can't captureBase64()");
+    }
+    if (!('renderBase64' in this.page)) {
+        this.warn('captureBase64() requires PhantomJS >= 1.6');
+        return;
+    }
     var base64;
     var previousClipRect;
     var formats = ['bmp', 'jpg', 'jpeg', 'png', 'ppm', 'tiff', 'xbm', 'xpm'];

@@ -11,7 +11,8 @@ casper.start('tests/site/index.html', function() {
     this.test.assert(fs.isFile(testFile), 'Casper.capture() captured a screenshot');
 });
 
-casper.thenOpen('tests/site/index.html', function() {
+if (phantom.version.major === 1 && phantom.version.minor >= 6) {
+    casper.thenOpen('tests/site/index.html', function() {
         this.test.comment('Casper.captureBase64()');
         this.test.assert(this.captureBase64('png').length > 0,
                          'Casper.captureBase64() rendered a page capture as base64');
@@ -19,7 +20,8 @@ casper.thenOpen('tests/site/index.html', function() {
                          'Casper.captureBase64() rendered a capture from a selector as base64');
         this.test.assert(this.captureBase64('png', {top: 0, left: 0, width: 30, height: 30}).length > 0,
                          'Casper.captureBase64() rendered a capture from a clipRect as base64');
-});
+    });
+}
 
 casper.run(function() {
     try {