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Connect timeout is limited by your OS's SYN retransmit count limit and timeout. Under FreeBSD it's 75s by default (3 retransmits with exponential backoff: 3s + 6s + 12s + 24s), under Linux it's looks like something about 20s by default. Looks like you are hitting this limit.
The only way to enlarge this limit is to tune OS, e.g. on Linux try adjusting net.ipv4.tcp_syn_retries sysctl.