Index: logback-access/src/main/java/ch/qos/logback/access/spi/AccessEvent.java
===================================================================
--- logback-access/src/main/java/ch/qos/logback/access/spi/AccessEvent.java	(revision 1601)
+++ logback-access/src/main/java/ch/qos/logback/access/spi/AccessEvent.java	(working copy)
@@ -212,7 +212,10 @@
   }
 
   public Enumeration getRequestHeaderNames() {
-    return httpRequest.getHeaderNames();
+	  if(httpRequest==null) {
+		  return null;
+	  }
+	return httpRequest.getHeaderNames();
   }
 
   public Map<String, String> getRequestHeaderMap() {
@@ -223,7 +226,10 @@
   }
 
   public void buildRequestHeaderMap() {
-    requestHeaderMap = new HashMap<String, String>();
+	requestHeaderMap = new HashMap<String, String>();
+	if(httpRequest==null) {
+		return;
+	}
     Enumeration e = httpRequest.getHeaderNames();
     if (e == null) {
       return;
@@ -235,8 +241,11 @@
   }
 
   public void buildRequestParameterMap() {
-    requestParameterMap = new HashMap<String, Object>();
-    Enumeration e = httpRequest.getParameterNames();
+	requestParameterMap = new HashMap<String, Object>();
+	if(httpRequest==null) {
+		return;
+	}
+	Enumeration e = httpRequest.getParameterNames();
     if (e == null) {
       return;
     }
@@ -247,11 +256,17 @@
   }
 
   public String getResponseHeader(String key) {
+	  if(serverAdapter==null) {
+		  return null;
+	  }
     return serverAdapter.getResponseHeader(key);
   }
 
   public List<String> getResponseHeaderNameList() {
-    return serverAdapter.getResponseHeaderNameList();
+	  if(serverAdapter==null) {
+		  return null;
+	  }
+	return serverAdapter.getResponseHeaderNameList();
   }
 
   /**
@@ -305,7 +320,7 @@
 
   public long getContentLength() {
     if (contentLength == SENTINEL) {
-      if (httpResponse != null) {
+      if (serverAdapter != null) {
         contentLength = serverAdapter.getContentLength();
         return contentLength;
       }
@@ -315,7 +330,7 @@
 
   public int getStatusCode() {
     if (statusCode == SENTINEL) {
-      if (httpResponse != null) {
+      if (serverAdapter != null) {
         statusCode = serverAdapter.getStatusCode();
       }
     }
@@ -327,8 +342,10 @@
     if (requestContent != null) {
       return requestContent;
     }
-
-    if (Util.isFormUrlEncoded(httpRequest)) {
+	if(httpRequest == null) {
+		return null;
+	}
+	if (Util.isFormUrlEncoded(httpRequest)) {
       StringBuffer buf = new StringBuffer();
 
       Enumeration pramEnumeration = httpRequest.getParameterNames();
@@ -380,12 +397,17 @@
       return responseContent;
     }
 
-    if (Util.isImageResponse(httpResponse)) {
+	if(httpResponse == null || httpRequest == null) {
+		return null;
+	}
+
+	if (Util.isImageResponse(httpResponse)) {
       responseContent = "[IMAGE CONTENTS SUPPRESSED]";
     } else {
 
       // retreive the byte array previously placed by TeeFilter
-      byte[] outputBuffer = (byte[]) httpRequest
+	  // TODO: please check if httpRequest below is correct.
+	  byte[] outputBuffer = (byte[]) httpRequest
           .getAttribute(Constants.LB_OUTPUT_BUFFER);
 
       if (outputBuffer != null) {