This is the strace from the executable using libcurl
it works without problems - here it gets the mozart-oz home page...

socket(PF_INET6, SOCK_DGRAM, 0)         = -1 EAFNOSUPPORT (Address family not supported by protocol)
socket(PF_UNIX, SOCK_STREAM, 0)         = 3
connect(3, {sa_family=AF_UNIX, path="/var/run/.nscd_socket"}, 110) = -1 ENOENT (No such file or directory)
socket(PF_INET, SOCK_DGRAM, IPPROTO_IP) = 3
connect(3, {sa_family=AF_INET, sin_port=htons(53), sin_addr=inet_addr("62.31.176.39")}, 28) = 0
send(3, "\250\310\1\0\0\1\0\0\0\0\0\0\3www\tmozart-oz\3org\0\0"..., 35, 0) = 35
recvfrom(3, "\250\310\201\200\0\1\0\2\0\0\0\0\3www\tmozart-oz\3org\0"..., 1024, 0, {sa_family=AF_INET, sin_port=htons(53), sin_addr=inet_addr("62.31.176.39")}, [16]) = 85
socket(PF_UNIX, SOCK_STREAM, 0)         = 3
connect(3, {sa_family=AF_UNIX, path="/var/run/.nscd_socket"}, 110) = -1 ENOENT (No such file or directory)
socket(PF_INET, SOCK_DGRAM, IPPROTO_IP) = 3
connect(3, {sa_family=AF_INET, sin_port=htons(53), sin_addr=inet_addr("62.31.176.39")}, 28) = 0
send(3, "\250\311\1\0\0\1\0\0\0\0\0\0\00268\003186\00296\003134"..., 44, 0) = 44
recvfrom(3, "\250\311\201\200\0\1\0\1\0\0\0\0\00268\003186\00296\003"..., 1024, 0, {sa_family=AF_INET, sin_port=htons(53), sin_addr=inet_addr("62.31.176.39")}, [16]) = 78
socket(PF_INET, SOCK_STREAM, IPPROTO_TCP) = 3
connect(3, {sa_family=AF_INET, sin_port=htons(80), sin_addr=inet_addr("134.96.186.68")}, 16) = -1 EINPROGRESS (Operation now in progress)
getsockopt(3, SOL_SOCKET, SO_ERROR, [0], [4]) = 0
send(3, "GET / HTTP/1.1\r\nHost: www.mozart"..., 127, 0) = 127
recv(3, "HTTP/1.1 200 OK\r\nDate: Fri, 05 A"..., 20479, 0) = 1448
recv(3, "\">Home</option>\n        <option "..., 20479, 0) = 1448
recv(3, "development\nplatform for intelli"..., 20479, 0) = 1448
recv(3, "p class=news>Current Mozart is 1"..., 20479, 0) = 1448
recv(3, "bsp;compatibility</span>\n<dd><sp"..., 20479, 0) = 1013