das läuft dann so ab:
du sendet mit libcurl du machst zuerst einen GET Request an die page: http://www.lokalisten.de dann bekommst du eine JSESSIONID .... diese brauchst du für den nächsten request!!

dann schickst du folgenden POST request an diese page:
http://www.lokalisten.de/j_security_check

POST /j_security_check HTTP/1.1
Host: www.lokalisten.de
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.0.6) Gecko/20060728 Firefox/1.5.0.6
Accept: text/xml,application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,/;q=0.5
Accept-Language: en-us,en;q=0.5
Accept-Encoding: gzip,deflate
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7
Keep-Alive: 300
Connection: keep-alive
Referer: http://www.lokalisten.de/web/showHome.do;jsessionid=2F767B191B80A909A8847ECCDA99B3A0.server1
Cookie: JSESSIONID=2F767B191B80A909A8847ECCDA99B3A0.server1
Content-Type: application/x-www-form-urlencoded
Content-Length: 37
j_username=username&j_password=passwd

username = dein benutzername
passwd = dein passwort

schaut dann ca so aus:

#include <string>
#include <iostream>
#include <cstdio>
#include <curl/curl.h>

using namespace std;

// libcurl.lib mitlinken!!

// This is the writer call back function used by curl
int writer(char *data, size_t size, size_t nmemb, string *buffer) {
	// What we will return
	int result = 0;

	// Is there anything in the buffer?
	if (buffer != NULL)
	{
		// Append the data to the buffer
		buffer->append(data, size * nmemb);

		// How much did we write?
		result = size * nmemb;
	}

	return result;
}

int main()
{
   CURL *curl_get;
   CURL *curl_post;
   CURLcode res;
   curl_slist *cookieptr;
   string cookieid;
   string buffer;

   curl_get = curl_easy_init();
   if(curl_get) {
     curl_easy_setopt(curl_get, CURLOPT_URL, "http://www.lokalisten.de");
	 curl_easy_setopt(curl_get, CURLOPT_USERAGENT, "User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.0.6) Gecko/20060728 Firefox/1.5.0.6");
	 curl_easy_setopt(curl_get, CURLOPT_COOKIEFILE, "");
	 curl_easy_setopt(curl_get, CURLOPT_HEADER, 1);
	 curl_easy_setopt(curl_get, CURLOPT_WRITEFUNCTION, writer);
	 curl_easy_setopt(curl_get, CURLOPT_WRITEDATA, &buffer);

	 res = curl_easy_perform(curl_get);

	 if(res != CURLE_OK) {
		curl_easy_cleanup(curl_get);
		cout << "Error: " << curl_easy_strerror(res) << endl;
		return -1;
	 }	

	 cout << "Server Response: " << '\n' << buffer << endl;

	 curl_easy_getinfo(curl_get, CURLINFO_COOKIELIST, &cookieptr);
	 if(cookieptr != 0) {
		cookieid = cookieptr->data;
		cookieid = cookieid.substr(34, 50);
		cookieid = cookieid.replace(10, 1, "=");
	 }

     /* always cleanup */
     curl_easy_cleanup(curl_get);

	 buffer.clear();
	 curl_post = curl_easy_init();
     if(curl_post) {
		curl_easy_setopt(curl_post, CURLOPT_URL, "http://www.lokalisten.de/j_security_check");
		curl_easy_setopt(curl_post, CURLOPT_USERAGENT, "User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.0.6) Gecko/20060728 Firefox/1.5.0.6");
		curl_easy_setopt(curl_post, CURLOPT_COOKIE, cookieid.c_str());
		curl_easy_setopt(curl_post, CURLOPT_POSTFIELDS, "j_username=username&j_password=passwd");
		curl_easy_setopt(curl_post, CURLOPT_HEADER, 1);
		curl_easy_setopt(curl_post, CURLOPT_WRITEFUNCTION, writer);
		curl_easy_setopt(curl_post, CURLOPT_WRITEDATA, &buffer);

		res = curl_easy_perform(curl_post);

		if(res != CURLE_OK) {
			curl_easy_cleanup(curl_post);
			cout << "Error: " << curl_easy_strerror(res) << endl;
			return -1;
		}	

		cout << "Server Response: " << '\n' << buffer << endl;

		/* always cleanup */
		curl_easy_cleanup(curl_post);
     }
   }

in curl_easy_setopt(curl_post, CURLOPT_POSTFIELDS
username durch deinen benutzernamen ersetzen!
passwd durch dein passwort ersetzen!

code ist jetzt nicht gerade schön;) soll nur zeigen wie es funzt;)

cu

so, habs probiert. hat aber nich gefunzt. bringt mir 230 fehler, von wegen unerwartetes ende